Sunday, December 22, 2013

If a Tree Falls in the Woods, Will the Tower Still Stand?

Last night the weather forecast was: "While a few, scattered showers cannot be ruled out throughout the evening and overnight...the main activity, in the form of heavier rain, strong gusty winds and perhaps even a few thunderstorms, won't near until 2-6 AM from west to east."  Specific forecast predictions said the wind would hit Huntington between 3 and 4 a.m. and Charleston between 4 and 5 a.m.  WELL - - - Just after 1 a.m. I was awakened by the house creaking and the sound of fast moving wind and rain.  It lasted until about 2 a.m. which was a good deal longer than I had expected.

Yesterday was the first official day of winter and record temperatures
were set in both Huntington and Charleston at 75°.  The National Weather Service Area Forecast Discussion for Charleston at 12:30 a.m. on Sunday did not think the winds were going to be significant:

Base of the Two Trees
However, local TV station WOWK-TV reported gusts as high as 60 mph and indicated the storm was moving across the area at 85 mph.  Only some 5,000 customers were without power however.

Center Section of the Trees
Once daylight returned, I took a look to see if my tower was still standing.  It was, but darned if it didn't look to be leaning just a little.  Further inspection showed a tree had fallen from my neighbor's property onto the Westerly set of guys for my tower. 

As you can see in the attached photos, the tree broke over about 5-1/2 to 6-feet above ground level.  This had actually happened in a previous storm and the tree had been supported at about a 60° angle by adjacent trees.  
Last night's storm finished the job of bringing it down.  As you can see in the third photo below, the top part of the trees were resting on the guys for my tower.  Click on any photo to see it larger.

Both of my go-to "Chain Saw Guys" were out of town so the job fell to me.  I began cutting the two trees (which had grown up together) about 2-feet above the ground to get them low enough so that they could be cut off the guys.  After I made my first wedge cut, I went back up the hill to get the gas can and bar oil for the chainsaw.  At that point my neighbor (who owned the land where the tree was) came to help and he did the rest of the cutting while I did the pulling and such. 
Top of Trees on Guy Wires

Eventually we were able to free the guy wires but they are quite slack.  I assume the tower has been pulled out of line and the guys may have been stretched due to the weight of the trees.  I will assess that situation later and see what needs to be done.  I'm just glad the tower is still standing!

I will need to go sight up the tower from the base and see how far it is out of line and see what can be done with the opposite guy wires to pull it back into line.  Then, I need to see if there was any damage to the Phillystran from the trees.  I saw nothing today but will want to check that just to be sure.

Could have been a WHOLE lot worse!

Friday, November 8, 2013

Recording QSO Audio on the K-3

An optional accessory for the Elecraft K-3 is the KDVR-3 Digital Voice Recorder.  The main purpose of this device is to record your voice and then play it back by pushing a button - a Voice Keyer.  However, it also has a feature where you can push a button (hold AF REC)and record the incoming rig audio.  Hold AF REC again to stop recording.  Push another button (hold AF PLAY) and it will play back that audio.  Hold AF PLAY again to stop the playback.  When in the playback mode, you can rotate the B VFO knob to select where in the 90 seconds you want to listen.  A "*" indicates you are in the most recent recording segment.

The recording can be up to 90 seconds in length and when it completes 90 seconds it just starts recording over what it previously recorded - a 90 second loop of the received audio.  Turn it on when you are about to call that rare DX and then turn it off after your QSO.  You can then easily play it back and see if he really did get your call correct.  You can also export the audio to your computer for archiving purposes (or to email to your buddies to brag about how well you copied the DX!)

Below is a link to an audio file (which I created using the KDVR-3) of my 80-M QSO with K9W on 8-Nov-2013 at 0800 GMT.  I recorded this because I was using a 160-M Inverted-L with a single elevated radial as my 80-M transmit/receive antenna.

Click HERE to listen to the audio.  Then use your BACK button to return to this page.

The trick to getting the audio out of the K-3 and into the computer is that you need to access the CONFIG : LIN OUT menu.  When you first access that menu it will probably read "nor 010" or something like that.  With that menu showing, you need to tap the "1" key.  The menu will now show "=PHONES" and that means the K-3 will feed the same audio that goes to the headphones to the LINE OUT jack on the back of the K-3.  This needs to be connected to your computer's LINE IN jack.  After you have exported the K-3 recorded audio to the computer, access the CONFIG : LIN OUT menu again and tap the "1" key to remove the "=PHONES" feature.  This puts the audio to your computer back to the normal level for PSK or other digital operation.

I use the program Audacity (which is a FREE program you can download from the Internet) to process and save my audio files.  Just "Google" the word "Audacity" for more info.  I run Audacity, start the Playback on the K-3, press the RECORD button in Audacity and then the STOP button when I reach the end of what I want to record.  I can now trim the audio as necessary and perform other operations on the audio file to make it more legible before saving it.

Thursday, November 7, 2013

New 160-M Inverted-L Installed

Since pretty much all the WVDXA members who are on 160-M have now worked K9W on Wake Island, I felt the pressure to snag a Top-Band QSO for myself.  After my success with the 40-M antenna yesterday, I felt that today was the day to put up an Inverted-L for 160-M.

Tim, K8RRT, volunteered to come with his bow and arrow and shoot a line over a likely tree.  I got everything ready and when Tim arrived about 3 p.m. we measured out 130-feet of No. 14 solid for the vertical element and a second length for the single elevated radial.

Over the hill, Tim took only 2 shots to place his arrow right where he wanted it.  We pulled back a small line and used that to pull the Dacron support line back over the tree.  The spot where Tim placed the arrow is probably 80-feet above ground.  Once the Dacron line was over the tree, I tied on the end of the vertical element and Tim pulled that over.  At that point, Tim had to leave but all that was left was for me to connect the coax to the remote antenna switch and run out the elevated radial.  It is no lower than 6 feet above ground and probably no higher than 10-feet.  I finished about 5:40 p.m. (just after sunset.)

Once back in the shack I ran an SWR plot which you can see above.  (Click on the photo for a larger image.)  An SWR of 1.69:1 at 1.800 MHz drops down to 1.49:1 at 1.820 MHz. and pretty much stays there up to 1.900 MHz where it is 1.42:1

UPDATE:  IT WORKS!  I was able to work K9W on 80-M using this 160-M Inverted-L for a New One.  Then, a little later, when they were calling CQ on 160-M, they sent "UP" and I sent my call ONE TIME and they came right back.  I would say this puppy WORKS!  Now, bring on T33A on Top-Band.  I'm a "Happy Camper" to be back on Top-Band.  Thanks, Tim!

New 40-M Wire Vertical Installed

     I've been building a 40-M wire vertical here in the house over the last few days and yesterday I installed it.  It is a 33.3-foot section of No. 14 stranded wire that stands off from the tower about 2-feet.  You can see the 2x2 treated boards that hold the top and bottom of the antenna in the photo on the right.  (Click on any photo to see a larger image.)  The bottom of the vertical is about 27-feet above ground and the top is about 60-feet.  I have two elevated radials attached and both slope down a little (they are not horizontal.)  I wanted to get it as high up in the air as possible because below 30-feet on the tower, everything to the West is blocked by my hill.

     The photo on the left above shows the RF Choke which is about 21 feet of coax wound on a 6-inch form - about 12 turns.  It is about 3-1/2 feet from the feedpoint of the antenna.  It is marked "Coil" in the photo of the tower.

     On the left is a plot of the SWR of this antenna.  The antenna is pretty flat from about 7.1 to 7.2 but at a 1.6:1 SWR.  It seems to be resonant about 7.125 MHz.  I was shooting for 7.025 MHz. and missed that by a good margin.  I'm guessing that the proximity of the tower is messing with the antenna both in the resonant point and in the pattern.  Still, it was easy to put this up (relatively easy - I am WAY out of shape!)

     But, it was good enough for me to have a QSO with K9W this morning on 40-M SSB.  The operator was Hal, W8HC, who was with me on Swains Island last year.  That was HUGE to be able to work him on Wake Island - AND that was a New One for me on 40-M!.  Obviously the antenna does get out as I only had to call twice to work him (at 43 minutes past my SR.)

     Here are some spot checks of the SWR:

7.000 - 2.25:1     7.100 - 1.61:1     7.200 - 1.59:1
7.025 - 2.00:1     7.125 - 1.41:1     7.225 - 1.71:1
7.050 - 1.88:1     7.150 - 1.46:1     7.250 - 1.77:1
7.075 - 1.66:1     7.175 - 1.55:1     7.275 - 1.83:1

Sunday, November 3, 2013

CW Skimmer's View of the 5JØR Pileup on 17-M

 At the left you can see a screen shot of CW Skimmer at K8RRT's QTH.  He was decoding the pileup for 5JØR, San Andres & Providencia, who was transmitting on 18.074 MHz.  It turns out that K9W, Wake Island, was also operational at the same time but the K9W station was not on 17-M at this particular time.  K9W's stated transmit frequency on 17-M is 18.079 MHz.  That would be square in the middle of the pileup on 5JØR!  (Click on any picture to see a larger image.)

On the right you can see the list of stations who were calling 5JØR, and who were being decoded by Tim's CW Skimmer program.  Who knows how many others were calling that Tim was not able to copy?  You can not see all the stations that CW Skimmer was decoding (see the extra yellow dots with no lines coming from them at the top of the image on the right) because Tim's monitor is not tall enough!

One interesting note is that while I was writing this Post, I was listening to 5JØR on 17-M.  By my count, he made 20 QSO's between the times when he sent his own call.  I looked at the clock when he made that second transmission of his callsign and then noted the time when he ID'd the next time.  12 minutes passed between those ID's!  Considering the potential for confusion on which station you worked when there are multiple DX'peditions on the air at the same time (and similar transmit frequencies), it would be better if ALL DX'peditions gave their calls more often.

Sunday, September 22, 2013

Testing the Tin Can Stove

Owen Stirring
Tin Can Stove in Operation
During the 2012-2013 winter, our grandsons, Owen and Grant, saw a video HERE on YouTube describing how to build a camp stove from a couple of tin cans.  They were fascinated and talked Evelyn into helping them make it as a "project."  I was called in to provide the tools (tin snips) but Evelyn and the boys did the rest.  The project was complete in a little over an hour but we waited for an opportune time to "test" out the stove.

Saturday night the boys came for a visit and brought the stove with them.  We were having hot dogs with homemade chili (sauce) for dinner so they decided to heat the hot dog chili with their stove.  It worked GREAT!  The pan they had which fit exactly on top of the stove was a bit small but it worked fine.  They just had to fill it three times to heat all the chili!

The stove consists of a Tuna Fish can with the tuna and the lid removed.  Cardboard is cut and wound inside the can in a spiral and then filled with melted candle wax.  The wicks from the melted candles  are placed in the center of the cardboard spiral to allow easy lighting of the stove.  A larger can has been cut (with the tin snips) to provide a place to slide the Tuna Fish can inside it.  Vent holes are cut into the top of the larger can with a can opener.  Then a piece of coat hanger is attached to the Tuna Fish can lid and the project is complete.

Grant Watching the Cook
As you can see, we put down some cardboard to protect the back porch from any "splatter" or "over-flow" from the stove.  The stove itself we sat on a paving stone so as to not set the cardboard on fire!  In the photo on the right where Grant is watching the stove, you can see that some of the candle wax has over-flowed from the small Tuna Fish can and it ran out on the paving stone.

In the photo on the upper-right which shows Owen stirring the chili, you can see the Tuna Fish can lid that is attached to a coat hanger sitting on the paving stone.  This is used to regulate the heat or to extinguish the flame.  It worked quite well.

Dinner was an absolute success!  And, after the stove was extinguished, there is still plenty of wax/cardboard "fuel" for a future "cook."

Click on any photo to see it larger.

Saturday, August 3, 2013

K-3 Rotating Macros

With the Elecraft K-3 you have the ability to write macros and load them into the transceiver using the Download and Configuration Utility.  "Macro" is short for "macroinstruction."  It is a set of individual instructions grouped together into one large instruction that can tell a computer (or the K-3) to do several things.  Once you load the macro to the K-3 you can then define a front panel button to execute the macro.

For some time I have been using two macros that I have configured to use the "PF1" and "PF2" buttons on the K-3's front panel.  One of them would automatically set the "A" and "B" VFO's to the same frequency, turn on the SHIFT, and move the "B" VFO up 2 kHz.  That way, if someone says "UP2" you can just hit 1 button and it will all be done in a flash.  I programmed the "PF1" button to shift UP 1 and "PF2" to shift UP 2 kHz.  It worked great.

Recently I became aware of some "special" coding of these macros which allowed them to perform more than just the one single set of instructions.  The "special" coding, in essence, would on the first push of the button execute the first part of the macro.  Then, the remainder of the macro would re-program the button to perform another function on the second push. 

I found many examples of macros in the K3 Configuration Utility Help file (Tab Pages | Command Tester/K3 Macros | Macro Buttons) as well as on KE7X's "Macro Repository" page HERE.  In the above referenced Help item there is the following statement:

A command memory may include commands to assign macros to buttons. This results in one button executing different command macros on successive button presses.
Think of it like a button that on the first push turns ON a lamp and on the next push, turns it OFF.  The Help file then gives references to posts by KU4AF HERE and K1HTV HERE that give details on how to do this.

I took what I saw in the above references and adapted it to my use and for loading into the "PF1" and "PF2" buttons.  The result was two separate "sets" of macros for the "PF1" and "PF2" buttons.  I could also have programmed the M1-M4 memory buttons but I wanted to keep those for accessing the Voice and CW Memories.

What I decided to do was to set up one macro to put the radio into Split and after that was completed, re-program the same button to perform a "Cleanup" on the next button push.  This "Cleanup" takes the radio out of Split mode and puts all the settings back to normal.  The second button would be programmed to put the radio into SSB, CW, DATA A (PSK-31), and RTTY modes on each successive button push.  To do this I had to set up 6 macros in the K-3 Configuration Utility.  Two of the macros are programmed into the "PF1" button  and 4 of them into the "PF2" button.  Those 6 macros perform as follows - PF1 is now the Split ON/OFF button and PF2 is the Change Mode button.  You can jump to the headings of "PF1 - - -"and "PF2 - - -" below in this Post to see each of those.

PF1 - - -
      Once these macros have been loaded, the "PF1" button now performs like this,

Press PF1 - the K-3 goes into Split Mode
Press PF1 again - the K-3 goes back to normal

     I have also changed what the K-3 does when it goes into Split Mode.  Now when I press PF-1 the first time it turns on the SUB receiver, puts the VFO A information into VFO B, goes into Split Mode, moves VFO B up 3 kHz (so this button can be used for both CW and SSB splits - you just have to move the VFO B knob to where you need to be), turns off the RIT and XIT, and LOCKS the VFO A knob so you can't accidentally move it and lose the DX station.  Pressing PF1 again will put everything back to normal.  It is so COOL!  You can move into Split Mode and back out with just a single button push plus you get all the other settings done at the same time with just one button!  AWESOME! 

     The big changes here are that the PF1 button now automatically turns on the SUB Receiver and LOCKS the "A" VFO so you can't accidentally lose the DX station.  A minor changes is that VFO B is now 3 kHz UP instead of just 1 or 2.  That way, if it is a CW station saying UP1, you just have to tune VFO B down 2 kHz.  If it is an SSB station saying UP5, then you just move the "B" VFO up 2 kHz.  That way this Split button works for both CW and SSB.  Heck, it even works for RTTY stations going split.

     Below are the details of the changes to the PF1 button.  First is a description of what is being done and then the Macro Label and actual Macro Commands are shown.  Anyone can simply Copy and Paste these from this Post into their K-3 Configuration Utility so the setup of these features is FAST!

CW Split starting point (UP 3)
This is a split variation contributed by Dave, N1LQ. Dave chose a compromise between the +2 and +5 versions. A quick twist of VFO B puts Dave up or down depending on CW or SSB.
SB1; turns the sub receiver on
SWT13; taps A>B once to copy VFO A frequency to VFO B
SWT13; taps A>B again to copy all other settings to VFO B
FT1; enters Split mode.
UPB6; moves VFO B up 3 kHz
RT0; turns RIT off
XT0; turns XIT off
LK1; locks VFO A to prevent changes to the receiver listening to the DX station in the heat of the pileup
     The following steps re-program the PF1 button to Macro #2
MN110; enters the CONFIG Menu
SWT12; taps the (2) button to choose Macro #2
SWH45; holds the PF1 button
SWT14; taps the Menu button

Macro Label #1 - Split+3

This is a "cleanup" macro contributed by Dave, N1LQ
SB0; turns the sub receiver off
FT0; turns split mode off
RT0; turns RIT off
XT0; turns XIT off
LN0; unlinks the VFOs
SQ000; turns squelch off
SWT13; taps A>B to copy VFO A frequency to VFO B
SWT13; taps A>B again to copy all other settings from VFO A to B
LK0; unlocks VFO A
     The following steps re-program the PF1 button to Macro #1
MN110; enters the CONFIG Menu
SWT11; taps the (1) button to choose Macro #1
SWH45; holds the PF1 button
SWT14; taps the Menu button

Macro Label #2 - Cleanup

PF2 - - - 
     Next is the change I made to the PF2 button.  Instead of just toggling ON and OFF like the PF1 button (turn ON Split Mode - turn OFF Split Mode), this PF2 button now switches the K-3 between USB, CW, Data-A (PSK-31), and RTTY modes in that order.

Press PF2 - the K-3 goes into USB Mode
Press PF2 again - the K-3 goes into CW Mode
Press PF2 again - the K-3 goes into DATA-A Mode (PSK-31 and other such modes)
Press PF2 again - the K-3 goes into RTTY Mode
Press PF2 again - the K-3 goes into USB Mode
. . . and so on

     This looks like a lot of work but it should make things VERY simple to switch from USB to CW to PSK-31 to RTTY and back.  But, remember - you do NOT need to use these buttons.  If you find that doing it the old way works better for you, then leave this alone. 

     Now that I have programmed my K-3 to do these functions, I'll be checking it out to see if I need to fine tune any of the parameters.  If anything needs to be changes, it's a simple thing to do.

Below is the detail for the four steps for the PF2 button:

Set SSB Parameters
MD2; selects USB mode
MN053; selects MIC SEL menu
DN; DN; moves the MIC SEL parameter down to Front Panel
UP; moves the MIC SEL up to Rear Panel (use this only if you are using the Rear MIC IN jack)
MG024; sets MIC Gain to "24" (insert appropriate numbers for your setup)
CP017; sets Speech Compression to "17" (insert appropriate numbers for your setup)
LK0; unlocks VFO A
BW0270; sets Bandwidth to 2.70 kHz.
     The following steps re-program the PF2 button to Macro #4
MN110; enters the CONFIG Menu
SWT24; taps the (4) button to choose Macro #4
SWH47; holds the PF2 button
SWT14; taps the Menu button

Macro Label #3 - USB-PF2

Set CW Parameters
MD3; selects CWmode
LK0; unlocks VFO A
BW0040; sets Bandwidth to 400 Hz.
KS022; sets Keyer Speed to 22 WPM
     The following steps re-program the PF2 button to Macro #5
MN110; enters the CONFIG Menu
SWT27; taps the (5) button to choose Macro #5
SWH47; holds the PF2 button
SWT14; taps the Menu button

Macro Label #4 - CW-PF2

Set DATA-A Parameters
MD6; selects DATA mode
DT0; selects Data-A sub-mode
MN053; selects MIC SEL menu
UP;UP; moves the MIC SEL parameter to Line In
BW0400; sets the Bandwidth to 4.0 kHz.
LK1; locks VFO A
     The following steps re-program the PF2 button to Macro #6
MN110; enters the CONFIG Menu
SWT29; taps the (6) button to choose Macro #6
SWH47; holds the PF2 button
SWT14; taps the Menu button

Macro Label #5 - DTA-PF2

Set RTTY ParametersMD6; selects DATA mode
DT2; selects FSK D sub-mode
BW0050; sets the Bandwidth to 500 Hz.
LK0; unlocks VFO A
     The following steps re-program the PF2 button to Macro #3
MN110; enters the CONFIG Menu
SWT13; taps the (3) button to choose Macro #3
SWH47; holds the PF2 button
SWT14; taps the Menu button

Macro Label #6 - RTT-PF2

Below are the 6 Macros that need to be loaded into the K-3 Configuration Utility.  
This can be done by Copy & Paste from this Post.

The  text labeled "Macro Label" goes into that field in the utility and the line underneath that is the actual macro text which goes into that field.

Macro Label #1 - Split+3

Macro Label #2 - Cleanup

Macro Label #3 - USB-PF2

Macro Label #4 - CW-PF2

Macro Label #5 - DTA-PF2

Macro Label #6 - RTT-PF2
After these Macros have been downloaded to the K-3, do the following on the K-3 itself:
On the K-3 go to CONFIG:MACRO
Press "1"
HOLD the PF1 key until "PF1 SET" appears
Tap the "Menu" key

Press "3"
HOLD the PF2 key until "PF2 SET" appears
Tap the "Menu" key

These steps assign the "Split" Macros to "PF1" and the "Mode Change" Macros to "PF2."  If you want to assign these steps to other buttons, you need to change some of the settings (like the SWT or SWH commands that emulate button pushes) in the above coding.

If you have other things you want to put into macros or you want to put some of the above programming into other buttons, you can find a list of all the button commands in the "K-3 Programmers Reference" which is available on the Elecraft web site.  I did not come up with these ideas, I just took what others have done and modified it to fit my particular use.

Friday, August 2, 2013

Logger32 Window for Control Of Alpha 87a

After doing the repair work on the Alpha 87a and hooking up the computer to talk to the amplifier, I remembered that my logging program, Logger32, has the ability to communicate to the Alpha 87a.  So, I enabled that window and was immediately in control of the amp.  As you can see in the photo, the amp is ON, in OPERATE, and HI POWER.  The AlphaMax feature is OFF.  The Fwd bar graph is indicating 1478 watts (according to the LP-100 wattmeter) and no reflected power is shown.

Logger32 Alpha 87a Control Window
One great feature of this window is that you can enable the "Auto Track Frequency" function.  According to Logger32's Help File, this feature:
. . . when turned on causes Logger32 to automatically supply the active radio's active VFO frequency to the amplifier, which uses that information to change bands and select settings for its TUNE and LOAD capacitors from user- or factory-preset values stored in internal 87A memory for each of five band segments on each band covered by the amplifier. Although the 87A is capable of changing bands automatically on its own by sensing the frequency of RF drive power from the transceiver connected to it, quicker band- and segment-changes that put less stress on the internal PIN-diode QSK system of the 87A and eliminate the loss of the first dash or dots on cw (while the amplifier takes itself off-line and retunes in response to sensing the newly selected operating frequency from input RF) are made possible by having Logger32 supply the transceiver's new frequency across the serial interface.
And, it works like a champ. Even with the 87a in STANDBY, when I change the frequency on the K-3, the Alpha tracks that change (courtesy of the "Auto Track Frequency" feature of Logger32) and the amp is immediately ready to transmit at full power. Awesome! It looks like I can click on a spot and hit transmit at full power without even the 1-1/2 second delay for the Alpha to tune to the new operating frequency or without the need to put any RF on the band to initiate tuning. But, the best thing is that it helps reduce the stress on the PIN diode QSK system in the amp.

One other big advantage of this window is that I can now see the status of the amplifier without turning around.  At my station the amp is pretty much behind me and it can "Fault" and go offline so quietly that I do not know when I'm no longer transmitting at full power.  Now I can see the power output and control the Standby/Operate switch right from the computer.  Plus, I can shut the amp OFF and even turn it ON from the Logger32 Control Window.  That's Just Sooo Cool!

Repairing the Alpha 87a - Round Two

I was floating along on a cloud after the successful repair of the Fault 1 problem (see Post below) but 12 days later, when attempting to power on the Alpha 87a, I got a "soft fault" designated as a No. 20 Fault Code.  The manual describes this as "Filament current greater than 3.5 amp. Possible shorted filament."  Bummer!  Did that mean I was going to have to replace one or both of the 3CX800A7's in the amp?  Eimac versions of those are now selling for $1,050 EACH but Alpha has just introduced their own line of tubes and I could get those for $400 each.  Still, that's a BIG expense.

Underneath View of Alpha 87a Tube Compartment
But, to look into the situation further, I did a Google Search for "Alpha 87a Fault 20" and found THIS page on Alpha's "Ask the Ham" web site which gave me hope.  Comments there from Alpha indicated that Fault 20 had not (in over 10 years) meant a bad tube.  It was related to connectors that needed to be cleaned.  Full instructions for doing this were included on the "Ask the Ham" site and included use of a product from Caig Laboratories called "Deoxit" which was available from Radio Shack.  Of course, my local "Shack" did not have the product so a brief 30-mile round trip was required to obtain the product.  This product is a 2-step operation.  One spray can contains a "Contact Cleaner and Rejuvenator" and the second can is a conditioner which enhances contact and seals the surfaces.

Now that I was ready to begin this new repair of the 87a I downloaded the PDF version of the manual from the Alpha web site to make it easier to read (on the computer instead of on paper.)  I then pulled the 75 pound amp off the shelf after disconnecting the cables including the AC.  Once again I needed to remove the "30" screws holding the cover to the chassis as well as four more screws that hold an access cover below the tube compartment.  But, I've been down this road many times before so it's getting to be old hat.

The high voltage crowbar activates when the cover is removed and should eliminate any residual high voltage within the amplifier but I also short the high voltage to ground in the area of the tube plates or the plate RF choke with an insulated screwdriver as an extra precaution as described in the manual.

Large Red Connectors on Control Board Need to be Reseated
This Fault 20 repair required me to remove 7 connectors underneath the tube compartment (see photo at upper left) as well as one on the low voltage power supply board, clean them with the Deoxit product and replace them.  I also needed to "re-seat" two connectors on the top edge of the control board (large red connectors in photo at right.)  In addition to "re-seating" those connectors, I cleaned the male pins with anhydrous alcohol and a Q-Tip.

Taking the photo at the upper left proved very useful to me.  When I cleaned and attempted to re-install one of the 7 connectors in the tube compartment, I was having difficulty getting it to fit on the male pins.  Then I noticed there were TWO male connectors on the board and I did not know which one was the correct one to accept the female connector.  Looking at the photo clearly showed me there was an extra (unconnected) male connector.  Also, and the reason I was having trouble plugging in the connector in the first place, the second connector is installed upside down (in relation to the correct one) and has more pins.  The correct one has the two center pin holes plugged so it cannot be plugged into the wrong connector.  Nice design by Alpha!

As an extra precaution, I put paper towels behind each connector while spraying it to make sure no "overspray" landed on any other components.  Alpha did not mention this but I decided to take this step purely as a precaution.

Once all the connectors were re-installed, it was time to put the "34" screws back into the covers and reconnect all cables (after hoisting the 75-pound amp back onto the shelf.)  I also took this opportunity to connect the Palstar AT-Auto tuner back into the station.  That is another complex piece of equipment that required me to review the manual and make a few changes to the default settings for my particular station.  One of those was to run the Keying Relay Input line for the Alpha 87a through the QRO Keyline circuit of the Palstar tuner.  This will inhibit the keying of the Alpha 87a while the Palstar is tuning.  Just one more piece of protection to keep me from hurting myself (or the Alpha) when (not IF) I make a mistake!
N8LP LP-100 Wattmenter Showing 1496 watts Output
As you can see in the final photograph, the Alpha 87a is again "back in service" and putting out the RF.  The amp has been ON for over 3 hours now and has been tested with full RF output a half dozen times and I have received ZERO Faults.  Yippee!

This entire operation took about 3 hours with about 2 of those spent on the actual dis-assembly/repair/reassembly of the Alpha 87a.  I am REALLY thankful I did not have to purchase new tubes and the repair only cost $15 for the Deoxit plus a trip to Cross Lanes.  I'd say that was more than reasonable!

One final thing I did was to connect the computer to the Alpha 87a and check the actual filament current.  Alpha suggests you check it several times so I made 15 checks of the filament current over a 5-minute period and saw values ranging from 2.70 amps to 3.01 amps.  Since the Fault Limit is 4.0 amps, I think the actual filament current is A-OK and the Fault 20 errors I received were erroneous and due completely to corrosion on one or more of the connectors in the amplifier.  Case closed!

Sunday, July 21, 2013

Repairing the Alpha 87a Amplifier

Recently I mentioned on the WVDXA Reflector that I was running barefoot because my Alpha 87a was on the sick list.  I was blown away by the many generous offers of help from WVDXA members.  People offered to lend me amplifiers from all corners of the state.  Those kind offers of help told me in no uncertain terms that the WVDXA as a whole sincerely wanted me to get out of the QRP category - and quickly!  That motivated me to move the repair of my Alpha 87a to the top of my list.

Click on any photo to see it larger.
Screws to Be Removed

I am embarrassed to say that my amp went out more than 20 MONTHS ago!  The issue was that as soon as the PTT line was keyed, the amp faulted and indicated the PIN back bias voltage was not at the minimum required level.  This is known as a Fault 1 problem.

When it got sick, Charlie, N8RR, took the amp in for repair.  He was able to reproduce the fault every time he keyed the amp.  As soon as he started measuring the R Bias voltage, he noticed a loose connection which he tightened up.  Once that was done, the Fault 1 problem never reappeared.  He tried the amp out at his QTH and it made full power with no trouble.  We both were relieved and thought Charlie had made a simple fix that solved the problem.

However, once the amp was back at my QTH, Mr. Murphy saw to it that the Fault 1 problem came back.  I took apart the R Bias connection that Charlie had found to be loose, thoroughly cleaned it and "firmly" tightened it back up - but the Fault 1 issue was still there.
T/R Module under Screening
At that time, RF Concepts (Alpha Amplifiers) said that if I shipped it to them for repair, it would sit in line for a minimum of 90 days before they could even begin the repair.  I figured I could probably fix it sooner than that so I just ordered all the parts that were listed in Alpha's "Troubleshooting Guide" for the Fault 1 problem as being possible failure points.  That was 4 PIN diodes, 1 power diode and 1 resistor.  Those six parts in their individual packing bags, failed to weigh even one ounce.  Still, it cost $65 to purchase them!

Once the parts had been received, I looked carefully at the procedure to replace everything and was dismayed.  5 of the 6 parts went on the T/R Module PC board which is a real bear to remove.  I have been in that compartment twice before over the 22+ years I have owned this amp and did not relish the job.  30 screws have to be removed just to get the cover off the amp.  Then another 15 or 20 screws, nuts, flat washers, and lock washers need to be removed.  Then, wires need to be unsoldered just to get at the PC board where the parts are to be replaced.   Finally, two smaller boards have to be removed along with the T/R Module.  I knew that I needed at least a couple of days where I would be doing NOTHING but working on this amp in order to have any chance of succeeding.  If I started this project and then let it sit while I tackled something else, I would end up with a box of parts and pieces that I could never get back together.  Plus, most of my free time in 2012 was taken up with the NH8S Swains Island DX'pedition.

I was not without an amp for the full 20 months as Charlie, N8RR, graciously lent me an AL-82 for about 6 months.  He would have let me use it longer but I knew that I had to return it or I would not get off my duff and repair the 87a!  Thanks Charlie!

T/R Module in Sub-Chassis
But, once I was spurred into putting this project on the front burner by the well wishes of the WVDXA, I decided to set aside this weekend to fix the Alpha.  I started bright and early on Friday and worked on the project until about 9 p.m.  I did not work constantly but took several breaks so that I did not get over-stressed.  Trying to get that T/R Module out of the metal sub-chassis it lives in nearly gave me hives!  At one point I sat and stared at the box for nearly an hour trying to figure out the best way to tackle that situation.  In the photo at the left you can see how the two smaller boards and the T/R Module are all shoe-horned into the metal sub-chassis.  I had instructions from Alpha on getting the sub-chassis out of the Alpha but no instructions on how to get the PC board out of the metal box.  You can also see the RF Input cable coming in from the bottom and the pin where it is soldered on the bottom left of the PC board.  You can also see the black "mistake mark" on the white wire above it.  Getting a small soldering iron into that space to unsolder that wire from that large pin was a challenge.

I was finally successful in getting the board out of the sub-chassis without breaking anything and with only one small burn to a wire (made by a slip of the soldering iron.)  Once it was free I took off a couple of hours to decompress!

When I came back to the project, it was not hard to remove the PIN diodes.  However, I found that two of them had resistors soldered directly (and tightly) across them.  I had not ordered replacement resistors so I needed to carefully unsolder those and salvage them for the new diodes.  That was tedious but again I was successful.  I was aided in removing the parts from the PC board by the fact that I had acquired (as a Christmas present several years ago) a neat desoldering tool.  This is basically a soldering iron which is hollow and has a vacuum pump attached to it.  Heat the joint with the iron and when the solder flows, hit the switch and suck the solder right out of the hole!  Amazing!

Diode/Resistor String I Built
I went to bed on Friday night after replacing the four PIN diodes (two with salvaged resistors across them - see photo at right) and one replacement resistor.  This left only one power diode replacement on the HV PC Board and putting everything back together.  Saturday morning I put the T/R Module back in the sub-chassis and it went in smooth as butter!  I was able to re-solder the wires without burning anything else and managed to put all the screws, nuts, bolts, flat washers and lock washers back with nothing left over.

Now I had to figure out how to remove the HV board.  Luckily I found several photos on the Internet (HERE) posted by a guy who had done that so my worries over how to remove that board were moot.  I pulled the HV board out in under 5 minutes (record time compared to the stress-filled adventure of taking out the T/R Module.)  Replacing the diode was done in about 10 minutes and the HV board went back without a hitch.

I took the opportunity during the repair to remove what dust I could from inside the amp.  In working on the T/R Module sub-chassis, I removed the 3CX800A7 tubes and gave them a thorough cleaning as well.  I used compressed air liberally to blow out what dust I could and used anhydrous alcohol to clean most things.  Once the repairs were completed, I spent about 15 minutes looking over everything to make sure I had not screwed up anything.  During that check I did find one cable I had forgotten to re-attach!  Whew!  Dodged a bullet there.

Trying to Get T/R Module OUT
I decided not to try and test anything but I just went ahead and completely re-assembled the amplifier including the 30 cabinet screws.  Once it was all back together, I lifted the monster up to my shelf and hooked up the RF Input and Output coaxes and the PTT Relay line.  I was ready to plug it in to the 220 VAC jack but now I had doubts.  I took a break and struggled with whether I had done all I could do and I wondered if being off for 20 months would have any negative effects on the amp.  But, I decided to give it a go anyway and I was within 2 minutes of plugging in the AC cable when the storm knocked out our power!  Was this an omen?  A sign?  A warning?  Who knew?

So, Evelyn and I left to run some errands and ended up at Pizza Hut in Milton (since Teays Valley, Scott Depot and Hurricane were all without power.)  We got home about 9:30 p.m. to find the power was back and after eating a bite I plugged in the amp and said a small prayer before pushing the switch. 

Lo and behold the amp fired up, went through its boot up sequence and I marveled at how nice those LED's looked after the amp was dark for close to 2 years.  When the time delay completed, and the amp switched to READY, there was a loud noise and the amp went dark.  RATS!  Murphy struck again. 

T/R Module Removed
It turned out that this Fault was a Fault 24 (System Voltage Fault) and I presumed that was due to the amp being off for so long and the capacitors had lost all their charge.  I bit my lip and powered it on again and this time it stayed on.  Hurray!

Now to see if I had managed to fix the Fault 1 issue.  I put the amp in operate and closed the PTT line with no drive applied.  20 months ago this would result in the amp Faulting with a Fault 1 code.  But, this time, NO FAULT!  Yippee!

Now to try the RF power test.  I had been planning to test on 30-M but moved the rig to 17-M instead.  That's where I made my first mistake.  I had turned down the power level of the K-3 to 5 watts but that was on 30-M.  On 17-M, the power level was still set to 109-watts!  As soon as I hit the PTT, the amp faulted with a Fault 14 code (Excessive load reflected power or RF voltage.)  Should have known that would happen.  65-watts of drive should give 1,500-watts out so 109-watts of drive was just a bit too much.

Technician At Work!
Finally, after correcting all my "cockpit errors", I managed to successfully operate the amp at over 400-watts output with 40-watts of drive.  The SWR was 3.22:1 on my 17-M dipole and the reflected power was about 130-watts so this was as high as I dared go until the antenna can be repaired.  I then moved to 30-M and with 8-watts drive achieved 196.5-watts output.

This testing was a bit limited, I was not able to test power output much over 400-watts, but I'm cautiously optimistic that once I correct the SWR problem on the 17-M antenna, I will be back in business.

In the photo of me working on the amp, note that I have added an LED headlamp just above my Optivisor.  That helps really put the light right on the spot where I need it!  And, I have made no mention of the screws I took out that did not need to be removed, nor the 8 or 9 items that I dropped and had to search for on the floor.  That's all forgotten now!

The next step is to hook up the Palstar AT-Auto tuner and get the 160-M Inverted-L back up.  That should let me operate at or near full power on most bands like I have done before.  This is, of course, a temporary situation.  My efforts now need to be directed to fixing the SteppIR so I can again have a "real" antenna on every band.

So, I give a great big "THANK YOU" to the WVDXA members for spurring me to finish this project.  The job was not as big as I had envisioned and I did not "kill" the amp while trying to repair it.   But, don't ask me to dig back into that T/R Module sub-chassis anytime in the next DECADE!

Tuesday, June 18, 2013

K8RRT Hits the Challenge!

Woooo, Hoooo!!!

K8RRT checked his LoTW account today and there it was, the 1,000th confirmation in his DXCC Award Account.  Tim now qualifies for the ARRL Challenge Award and can get that fancy plaque for his wall.

Nice going, Tim.  Now you can start working on the next 500 so you can get your first Medallion for your shiny new plaque.

Sunday, June 16, 2013

Kid's Day - 2013

For the last week, my grandsons, Owen and Grant, have been studying the Morse Code.  I thought it would be good to let them join in on the ARRL Kid's Day activities to go along with their studies so they could get a feel of what Ham Radio is all about.

Grant Calling "CQ Kid's Day"
Since my station is not fully operational, Tim, K8RRT, lent me his station for the day.  The boys and I arrived about 1:45 p.m. and began booting up the equipment and computers.  Tim has a very extensive computer interface to his station and the boys were interested in all aspects of that.  (Click on any photo to make it larger.)

Once the station was operational, we went over how they would talk on the radio.  Tim uses a footswitch to key the transmitter so they had to learn to step on that switch when they wanted to talk.  We also went over the basics of what they needed to say in the QSO's and I created a short "cheat sheet" for them to follow.  You can see the "Cheat Sheets" lying on the keyboard.  They only looked at that sheet for the first few QSO's because they had memorized everything they needed to say.

Owen Listening for a Call
We set up the amp and ran about 1,200 watts so the boys would be heard well even if they didn't talk very loud.  After a few QSO's they asked if they could not wear the headset because we were listening to the speakers.  When doing that, they sometimes talked into the back of the microphone and did not produce a very strong signal.  I showed them the Power Out meter on the amp and explained how it had to move strongly up scale for them to be heard and that did it - they spoke louder and more into the mic after that!

Since the same day was also the West Virginia QSO Party, we had a couple of stations ask the boys what County they were in so they could count the QSO in the WVQP.  Owen then decided to simply say, "I'm located in Hurricane, West Virginia, and that's in Putnam County" with each of his QSO's!

During the video below, you can hear that Owen actually had a pileup coming back to him plus a WA6 station even called in during his QSO.  The recorded audio is a bit low so you might need to "Crank It Up" to hear everything.

Near the end of our operating time we even managed a QSO with the Dorothy Grant Elementary School in Fontana, CA.  That school has their own Ham Radio Club and uses the callsign, K6DGE.  HERE is their web site.  Back in April I was privileged to attend one of their Field Day events where the kids learned electronics, built an antenna and operated the radio.

We had to leave the air by 4 p.m. because the boys had other engagements.  They had paid close attention to our startup of all Tim's equipment and they helped me shut everything down.  In fact, Grant spotted that I had left the rotor turned on and brought that to my attention before we left.

Later, at the Dairy Queen, where we were enjoying a celebratory Blizzard after our Kid's Day operation, Grant looked up at me and said, "Grandpa, I had a really good time!"  Yep, that's what it's all about, folks!  Ham Radio is about having a Good Time!