Traditionally held on “The Last Rainy Weekend” in June but for the sticklers for the rules its actual date is the 4th weekend in June…

This year it would be on June 22nd and ending on June 23rd

So what will VA3QV be doing???? Its safe to say that my Field Day Station will look a bit like this:

or like this from back in 2017….

So I plan to be operating as a 1B Battery Station from the RAC Ontario East Section (ONE)

The actual location has not been determined yet but there is a good chance the location could be one of the Parks on the Air location in the City of Kingston.

That’s the plan for good weather… and so far the long range forecast is calling for nice (dry). If the weather is not dry then the plan is to operate as a home station in the 1D catagory just to give out points to the participants

If you are new at this then the rules can be found here:

Years ago Field Day was considered a test of our emergency operating skills specifically to set up and operate a station for 24 hours and somehow it has morphed into more of contest with groups of operators putting up equipment that would not be used in a real emergency at power levels that could not be maintained unless you had a generator and an endless supply of gasoline.

I’m a little more primitive by setting up my QRP (5w of power) radio with a wire antenna and using a solar panel to top up the battery as needed.

I will have the option of being under cover (see above pic) as protection from the sun and/or rain most likely be needed at some time . Not sure how long I will be operating but it won’t be for the full 24 hours.

Overnight all I would be doing is listening to static and feeding the mosquitoes…

No egos to stroke…. Just operate and make some contacts with the emphasis of having fun and not taking myself too seriously.

Hope to hear you and be heard by you during the event

73bob

Well its not as bad as indicated from my last post…

But its still got a way to go…

This morning on my 11 am (Eastern) hour on the TPN I managed to get 7 stations in my log which is the best its been in a while. After the net ended I had some household chores to do before I could get to the next part of this post.

Today I wanted to take my Yaesu FT891 rig along with my two antennas out into my backyard and make sure everything is still working as well as I remember. Next week my shifts on the TPN will be ending for a while as I am taking the summer off in an attempt to concentrate on my POTA part of the hobby.

So here’s the setup

Rig: Yaesu FT891 powered by my ECO-Worthy 20ah LI-PO4 battery

Antenna 1: 40m EFHW which is 63 feet long and fed by a 64:1 unun. This antenna usually is used in a sloper or inverted Vee configuration. Its very nice on 10-40m and I have 2 small counterpoises which I clip on as needed. I feed the unun from a 25 foot run of RG58 with a RF choke at one end.

Antenna 2: 17.5 foot long end fed fed by a 9:1 unun. I normally would use this in a vertical or sloper configuration. Its excellent on 10m to 20m but will also work on 40m without the need of a tuner. Depending on the situation I have a couple of small counterpoises I can clip onto the unn if needed. I feed the unun from a 25 foot run of RG58 with a RF choke at one end. The advantage to this antenna is that if I use it as a vertical there is next to no footprint which could make a couple of the parks in the downtown area much easier to activate.

If the trees do not cooperate I also carry a MFJ 33 foot telescopic masting which will support the wire if needed.

How did I do today?

Operating from my deck I strung out the 63 foot EFHW kind of as an inverted xyz configuration. Hanging 63 feet of wire anywhere I could hand it without anyone seeing it or running into it. Despite the setup Contacts were made on 40m and 20m despite the band conditions. with a reasonable SWR (no tuner in line) where I normally use it

Next I used the 17.5 with the 9:1 unun as a low sloper and made 1 contact on 20. The SWR was “tolerable” on 40m but on 10m to 20m it was under 2:1 which is great for a Portable setup. Nothing to complain about on my part.

I also use this style of antenna at home in a vertical configuration and it works great for my need either “home or away”

So here’s the plan…

If you notice the above map there are 10 POTA sites (yellow dots) that I can easily access from my home in Kingston. All of them easily reachable via public transit or a bit of a walk. The one on the bottom right (the island) is not reachable via foot. There is a dock but I can’t find out if Kingston has a Water Taxi so if I can activate 10 out of 11 I will be pleased.

I guess I could also say that this would be a test of the station I will be using for Field Day this year. Not sure where I’m going to be yet but…. I know I’ll be participating from somewhere near Kingston.

.

Till next time

73bob

Well its not as bad as indicated from my last post…

But its still got a way to go…

This morning on my 11 am (Eastern) hour on the TPN I managed to get 7 stations in my log which is the best its been in a while. After the net ended I had some household chores to do before I could get to the next part of this post.

Today I wanted to take my Yaesu FT891 rig along with my two antennas out into my backyard and make sure everything is still working as well as I remember. Next week my shifts on the TPN will be ending for a while as I am taking the summer off in an attempt to concentrate on my POTA part of the hobby.

So here’s the setup

Rig: Yaesu FT891 powered by my ECO-Worthy 20ah LI-PO4 battery

Antenna 1: 40m EFHW which is 63 feet long and fed by a 64:1 unun. This antenna usually is used in a sloper or inverted Vee configuration. Its very nice on 10-40m and I have 2 small counterpoises which I clip on as needed. I feed the unun from a 25 foot run of RG58 with a RF choke at one end.

Antenna 2: 17.5 foot long end fed fed by a 9:1 unun. I normally would use this in a vertical or sloper configuration. Its excellent on 10m to 20m but will also work on 40m without the need of a tuner. Depending on the situation I have a couple of small counterpoises I can clip onto the unn if needed. I feed the unun from a 25 foot run of RG58 with a RF choke at one end. The advantage to this antenna is that if I use it as a vertical there is next to no footprint which could make a couple of the parks in the downtown area much easier to activate.

If the trees do not cooperate I also carry a MFJ 33 foot telescopic masting which will support the wire if needed.

How did I do today?

Operating from my deck I strung out the 63 foot EFHW kind of as an inverted xyz configuration. Hanging 63 feet of wire anywhere I could hand it without anyone seeing it or running into it. Despite the setup Contacts were made on 40m and 20m despite the band conditions. with a reasonable SWR (no tuner in line) where I normally use it

Next I used the 17.5 with the 9:1 unun as a low sloper and made 1 contact on 20. The SWR was “tolerable” on 40m but on 10m to 20m it was under 2:1 which is great for a Portable setup. Nothing to complain about on my part.

I also use this style of antenna at home in a vertical configuration and it works great for my need either “home or away”

So here’s the plan…

If you notice the above map there are 10 POTA sites (yellow dots) that I can easily access from my home in Kingston. All of them easily reachable via public transit or a bit of a walk. The one on the bottom right (the island) is not reachable via foot. There is a dock but I can’t find out if Kingston has a Water Taxi so if I can activate 10 out of 11 I will be pleased.

I guess I could also say that this would be a test of the station I will be using for Field Day this year. Not sure where I’m going to be yet but…. I know I’ll be participating from somewhere near Kingston.

.

Till next time

73bob

If you look back to my previous post in which I had covered my successful POTA activation of CA5143 I mentioned that I had used my 40m EFHW antenna to make the 23 contacts made.

Well one thing I neglected to mention was the difficulty I had getting 62 feet (or so) wire stretched out in the rather dense brush just off the trail. In the past I had mentioned about getting a 2nd antenna in the kit for when the EFHW was just not able to be deployed easily.

I had tried a BuddiPole but it did not (could not) do exactly what I wanted…. Using some parts from the BuddiPole and then adding a “Imitation” Shock Corded 9 foot whip (In my opinion…FWIW the Amazoon 9.5 ft shock cord whip is a real POS)was not doing it for me either. I tried following the instructions and when those did not work I tried (to no avail) to use what I tried in the past with other portable antennas but just no joy…

Fast forward to yesterday. The LDG 9:1 UNUN that I ordered on the Monday had arrived and so I decided to duplicate the “Coastal-20” antenna that I use at home for 10-12-15-17 & 20m. If you “Google Coastal-20 you should see the basic plans. Its a 9:1 UNUN along with a 17.5 foot vertical with a short counterpoise.

Now on my first build I found the short counterpoise version did not perform exactly as I had hoped so I decided to go with 3 elevated counterpoises. I cut 1 for 10-15 &20m and it worked quite well for me on 10 to 20m. By well I mean that I was making contacts and the SWR on all the needed bands was low or low enough that the internal tuner in my Yaesu FT991a was handling it.

Mostly copying my first version with the exception of swapping out 3 counterpoises for a single 11 foot counterpoise seemed to make no difference with the SWR and it was loading up just as well as the previous one did.

The next test for the new antenna will be when I get out into the Park (hopefully this weekend) if the forecasted rain ever stops. The plan is to have both antennas available for when I participate in the POTA Support your Parks event which happens April 20th and 21st and by strange luck is also the same weekend as the Ontario QSO Party, The Michigan QSO Party and the Quebec QSO Party so there should be no problems getting contacts to activate what ever park (parks) I head out to…

73bob

This was a special one for me. The last I tried to activate the Marshlands Conservation Area I had an equipment malfunction and as such it was a “Failed Activation”.

Today I headed out to get the one that got away.

I set up (red dot on the map) and operated with my FT891 set at 30w , 40m EFHF and proceeded to give out contacts….

In one hour I had managed to make 23 contacts in Ontario, and the Eastern Parts of the USA.

In the “learning part” of my activation I still have to find a way to carry more stuff and also make the kit lighter… It was a 4 km walk there and back (thats almost 2.5 miles to those of you south of the border) and to be honest I was really glad to get home and get my feet up.

I mentioned a few posts back about using some sort of trailer to carry the kit and today’s effort reinforces that thought….

Anyway I did have fun…. and if I worked you I hope you had fun as well….. If you don’t see our QSO today in your Hunters Log let me know and I’ll try to figure out why not…

73bob

A Coronal Mass Ejection (or other solar phenomena) has rendered the bands positively yucky today. But for the limited amount of time that I spent behind the key today, I still managed to snare six POTA stations for the log.

WD8RIF at US-1994

K2EAG at US-1619

KU8T at US-1637

WI2X at US-1611

AE4WX at US-6962

W0ABE at US-10533

All contact were made on 30 and 20 Meters. I heard EA4HCF calling CQ on 17 Meters and I tried answering, but no joy at 5 Watts. For the heck of it, I tried bumping up the KXPA100 to 85 Watts, just to see if I could make contact. Nope - that tells you that the bands truly did bite. I usually rarely have a problem reaching Spain with 5 Watts, let alone 85 Watts.

Last week the POTA powers-that-be changed all the designators from "KA" to "US". Earlier in the month, they changed Canada from "VE" to "CA" and all of Great Britain from "G" to "GB". Not exactly sure what was the reasoning, but I'm sure they had a good one.

It will be interesting to see if I hear anyone on the St. Max Net tonight on 75 Meters.

I was going to go out today and play around with the Buddistick on top of the Jeep, using that magmount  on which I replaced the coax cable. It's in the upper 40s and normally, that wouldn't be too terrible. We're getting a steady breeze and wind gusts that are making it downright uncomfortable to be outside. This is the day after that Nor'Easter blew through here yesterday, dropping 2.72 inches of rain on my QTH. I'm hoping that maybe next weekend will be warm enough for me to run some quick tests without allowing my hands to go numb.

72 de Larry W2LJ

QRP - When you care to send the very least!

Recently, a Kenwood TS-850S - a radio from the mid-early 1990s - crossed my workbench.  While I'm not in the "repair business", I do fix my own radios, those of close friends, and occasionally those of acquaintances:  I've known this person for many years and we have several mutual friends.

If you are familiar with the Kenwood TS-850S to any degree, you'll also know that they suffer from an ailment that has struck down many pieces of electronic gear from that same era:  Capacitor Plague.

Figure 1: The ailing TS-850S.  The display is normal - except for the frequency display showing only dots.  This error is accompanied by "UL" in Morse. Click on the image for a larger version.

The underlying cause?

While "failure by leaking" is a common occurrence in electronics, this failure is somewhat different in many aspects.  At about this time, electronic manufacturers were switching over to surface-mount devices - but one of the later components to be surface-mounted were the electrolytic capacitors themselves:  Up to this point it was quite common to see a circuit board where most of the components were surface-mount except for larger devices such as diodes, transistors, large coils and transformers - and electrolytic capacitors - all of which would be mounted through-hole, requiring an extra manufacturing step.

Early surface-mount electrolytic capacitors, as it turned out, had serious flaws.  In looking at the history, it's difficult to tell what aspect of their use caused the problem - the design and materials of the capacitor itself or the method by which they were installed - but it seems that whatever the cause, subjecting the capacitors themselves to enough heat to solder their terminals to the circuit board - via hot air or infrared radiation - was enough to compromise their structural integrity.

Whatever the cause - and at this point it does not matter who is to blame - the result is that over time, these capacitors have leaked electrolyte onto their host circuit boards.  Since this boron-based liquid is somewhat conductive and mildly corrosive in its own right, it is not surprising that as surface tension wicks this material across the board, it causes devastation wherever it goes, particularly when voltages are involved.

The CAR board - the cause of "display dots"

In the TS-850S, the module most susceptible to leaking capacitors is the CAR board - a circuit that produces multiple, variable frequency signals that feeds the PLL synthesizer and several IF (Intermediate Frequency) mixers.  Needless to say, when this board fails, so does the radio.

They most obvious symptom of this failure is when damage to the board is so extensive that it can no longer produce the needed signals - and if one particularly synthesizer (out of four on the board) fails, you will see that the frequency display disappears - to be replaced with just dots - and the letters "UL" are sent in Morse Code to indicate the "Unlock" condition by the PLL.

Figure 2: The damaged CAR board.  All but one of the surface-mount electrolytic capacitors has leaked corrosive fluid and damaged the board.  (It looked worse before being cleaned!) Click on the image for a larger version.

Figure 2 shows what the damaged board looks like.  Actually, it looked a bit worse than that when I first removed it from the radio - several pins of the large integrated circuits being stained black.  As you can see, there are black smudges around all (but one) of the electrolytic capacitors where the corrosive liquid leaked out, getting under the green solder mask and even making its way between power supply traces where the copper was literally being eaten away.

The first order of business was to remove this board and throw it in the ultrasonic cleaner.  Using a solution of hot water and dish soap, the board was first cleaned for six minutes - flipping the board over during the process - and then very carefully, paper towels and then compressed air was used to remove the water.

Figure 3: The CAR board taking a hot bath in soapy water in an ultrasonic cleaner.  This removes not only debris, but spilled electrolyte - even that which has flowed under components. Click on the image for a larger version.

If you look at advice online, you'll see that some people recommend simply twisting the capacitor off the board as the most expedient removal procedure, but I've found that doing so with electrolyte-damaged traces often results in ripping those same traces right off the board - possibly due to thinning of the copper itself and/or some sort of weakening of the adhesive:  While I was expecting chemically-weakened traces, already, there was no reason to add injury to insult.

My preferred method of removing already-leaking capacitors is to use a pair of desoldering tweezers, which are more or less a soldering iron with two prongs that will heat both pins of the part simultaneously, theoretically allowing its quick removal.  While many capacitors are easily removed with this tool, some are more stubborn:  During manufacture, drops of glue were used under the part to hold it in place prior to soldering and this sometimes does its job too well, making it difficult to remove it.  Other times, the capacitor will explode (usually just a "pop") as it is being heated, oozing out more corrosive electrolyte.

With the capacitors removed, I tossed it in the ultrasonic cleaner for other cycle in the same warm water/soap solution to remove any additional electrolyte that had come off - along with debris from the removal process.  It is imperative when repairing boards with leaking capacitors that all traces of electrolyte be completely removed or damage will continue even after the repair.

At this point one generally needs to don magnification and carefully inspect the board.  Using a dental pick and small-blade screwdriver, I scraped away loose board masking (the green overcoating on the traces) as well as bits of copper that had detached from the board:  Having taken photos of the board prior to capacitor removal - and with the use of the Service Manual for this radio, found online - I was confident that I could determine where, exactly, each capacitor was connected.

When I was done - and the extent of the damage was better-revealed - the board looked to be a bit of a mess, but that was the fault of the leaking capacitors.  Several traces and pads in the vicinity of the defunct capacitors had been eaten away or fallen off - but since these capacitors are pretty much placed across power supply rails, it was pretty easy to figure out where they were supposed to connect.

Figure 4: The CAR board, reinstalled for testing. Click on the image for a larger version.

The photo shows the final result.  Different-sized capacitors were used as necessary to accommodate the available space, but the result is electrically identical to the original.  It's worth noting that these electrolytic capacitors are in parallel with surface-mount ceramic capacitors (which seem to have survived the ordeal) so the extra lead length on these electrolytics is of no consequence - the ceramic capacitors doing their job at RF as before.  After (later) successful testing of the board, dabs of adhesive were used to hold the larger, through-hole capacitors to the board to reduce stress on the solder connections under mechanical vibration.

Following the installation of the new capacitors, the board was again given two baths in the ultrasonic cleaner - one using the soap and water solution, and the other just using plain tap water and again, the board was patted dry and then carefully blown dry with compressed air to remove all traces of water from the board and from under components and then allowed to air dry for several hours.

Testing the board

After using an ohmmeter to make sure that the capacitors all made their proper connections, I installed the board in the TS-850S and... it didn't work as I was again greeted with a "dot" display and a Morse "UL".

I suspected that one of the "vias" - a point where a circuit traces passes from one side to another through a plated hole - had been "eaten" by the errant electrolyte.  Wielding an oscilloscope, I quickly noted that only one of the synthesizers was working - the one closest to connector CN1 - and this told me that at least one control signal was missing from the rest of the chips.  Probing with the scope I soon found that a serial data signal ("PDA") used to program the synthesizers "stopped" beyond the first chip and a bit of testing with an ohmmeter showed that from one end of the board to the other, the signal had been interrupted - no doubt in a via that had been eaten away by electrolytic action.

Figure 5: Having done some snooping with an oscilloscope, I noted that the "PDA" signal did not make it past the first of the (large) synthesizer chips.  The white piece of #30 Kynar wire-wrap wire was used to jump over the bad board "via" Click on the image for a larger  version.

The easiest fix for this was to use a piece of small wire - I used #30 Kynar-insulated wire-wrap wire (see Figure 5) - to jumper from where this control signal was known to be good to a point where it was not good (a length of about an inch/two cm) and was immediately rewarded with all four synthesizer outputs being on the correct frequencies, tuning as expected with the front-panel controls.

Low output

While all four signals were present and on their proper frequencies - indicating that the synthesizers were working correctly - I soon noticed, using a scope, that the second synthesizer output on about 8.3 MHz was outputting a signal that was about 10% of its expected value in amplitude.  A quick test of the transmitter indicated that the maximum RF output was only about 15 watts - far below that of the 100 watts expected.

Again using the 'scope, I probed the circuit - and comparing the results with the nearly identical third synthesizer (which was working correctly) and soon discovered that the amplitude dropped significantly through a pair of 8.3 MHz ceramic filters.

The way that synthesizers 2 and 3 work is that the large ICs synthesize outputs in the 1.2-1.7 MHz area and mix this with a 10 MHz source derived from the radio's reference to yield signals around 8.375 and 8.83 MHz, respectively - but this mix results in a very ugly signal, spectrally - full of harmonics and undesired products.  With the use of these ceramic bandpass filters - which are similar to the 10.7 MHz filters those found in analog AM and FM radios - and these signals are "cleaned up" to yield the desired output over a range of the several kiloHertz that they vary depending on the bandpass filter and the settings of the front panel "slope tune" control.

Figure 6: The trace going between C75 and CF1 was cut and a bifilar- wound transformer was installed to step up the impedance from Q7 to that of the filter:  R24 was also changed to 22 ohms - providing the needed "IF-7-LO3" output level at J4. Click on the image for a larger version.

The problem here seemed to be that the two ceramic 8.3 MHz filters  (CF1, CF2) were far more lossy than they should have been.  Suspecting a bad filter, I removed them both from the circuit board and tested them using a temporary fixture on a NanoVNA:  While their "shape" seemed OK, their losses were each around 10dB more than is typical of these devices indicating that they are slowly degrading.  A quick check online revealed that these particular frequency filters were not available anywhere (they were probably custom devices, anyway) so I had to figure out what to do.

Since the "shape" of the individual filter's passbands were still OK - a few hundred kHz wide - all I needed was to get more signal:  While I could have kludged another amplifier into the circuit to make up for the loss, I decided, instead, to reconfigure the filter matching.  Driving the pair of ceramic filters is an emitter-follower buffer amplifier (Q7) - the output of which is rather low impedance - well under 100 ohms - but these types of filters typically "want" around 300-400 ohms and in this circuit, this was done using series resistors - specifically R24.  This method of "matching" the impedance is effective, but very lossy, so changing this to a more efficient matching scheme would allow me to recover some of the signal.

Replacing the 330 ohm series resistor (R24) with a 22 ohm unit and installing a bifilar-wound transformer (5 turns on a BN43-2402 binocular core) wired as a 1:4 step-up transformer (the board trace between C75 and CF1 was cut and the transformer connected across it) brought the output well into the proper amplitude range and with this success, I used a few drops of "super glue" to hold it to the bottom of the board.  It is important to note that I "boosted" the amplitude of the signal prior to the filtering because to do so after the filtering - with its very low signal level - may have also amplified spurious signals as well - a problem avoided in this method.

Rather than using a transformer I could have also used a simple L/C impedance transformation network (a series 2.2uH inductor with a 130pF capacitor to ground on the "filter side" would have probably done the trick) but the 1:4 transformer was very quick and easy to do.

With the output level of synthesizer #2 (as seen on pin CN4) now up to spec (actually 25% higher than indicated on the diagram in the service manual) the radio was now easily capable of full transmit output power, and the receiver's sensitivity was also improved - not surprising considering that the low output would have starved mixers in the radios IF.

A weird problem

I know that the problem is NOT the CAR board or the PLL/synthesizer itself as these are being properly set to frequency.  What seems to NOT be happening is that for the non-working adjustments, the radio's CPU is not adjusting the tuning of the radio to track the shift of the IF frequency to keep the received signal in the same place - which seems like more of a software problem than a hardware problem:  Using the main tuning knob or the RIT one can manually offset this problem and permit tuning of both the upper and lower slopes of of the filters, but that is obviously not how it's expected to work!

In searching the Internet, I see scattered mentions of this sort of behavior on the TS-850 and TS-950, but no suggestions as to what causes it or what to do about it:  I have done a CPU reset of the radio and disconnected the battery back-up to wipe the RAM contents, but to no avail.  Until/unless this can be figured out, I advised the owner to set the affected control to its "Normal" position.  If you have experienced this problem - and especially if you know of a solution - please let me know.

Figure 7: The frequency display shows that the synthesizer is now working properly - as did the fact that it outputs full power and gets good on-the-air signal reports. Click on the image for a larger version.

Final comments

Following the repair, I went through the alignment steps in the service manual and found that the radio was slightly out alignment - particularly with respect to settings in the transmit output signal path - possibly during previous servicing to accommodate the low output due to the dropping level from the CAR board.  Additionally, the ALC didn't seem to work properly - being out of adjustment - resulting in distortion on voice peaks with excessive output power.

With the alignment sorted, I made a few QSOs on the air, getting good reports - and using a WebSDR to record my transmissions, it sounded fine as well.

Aside from the odd behavior of the "Slope Tune" control, the radio seems to work perfectly.  I'm presently convinced that this must be a software - not a hardware - problem as all of the related circuits function as they should, but don't seem to be being "told" what to do.

* * * * *

This page stolen from ka7oei.blogspot.com

[END]

I’ve been wanting to tidy up the cabling to the 12v DC PSU for some time in the radio shack as like many HAMs I have a number of radios/devices that all need a 12v feed but, only two connectors on the front of the PSU. The net result was a birds nest of wires all connected to the PSU making it impossible to disconnect one device without others getting disconnected at the same time.

Looking online I found that many of the HAM outlets stores sell nice little 12v DC distribution boxes that would be ideal however, they’re all priced somewhat high for what they are so, I decided to purchase the parts and make one myself.

Searching on Amazon I found all the necessary parts for less than a quarter of the cost of commercially made units. A couple of days later the parts arrived and sat on my desk in the shack for a few weeks. Yesterday I finally found the time to make a start on the project.

After much drilling and filing I had the necessary holes/slots cut in the plastic box for the 4mm connectors and fuse holders and started wiring them up. Part way through my 30 year old soldering iron decided to die and so I had to stop and wait for a replacement to arrive.

With the new soldering iron in hand it only took 30mins or so to complete all the joints and I soon had the box together ready to test with my multimeter to ensure I didn’t have any shorts or crossed wires.

With testing complete and fuses in place I connected it up to the PSU and then connected all the devices one by one checking for voltage drops as I went.

I now have my CG3000 remote auto ATU, GPSDO, QO-100 ground station and IC-705 all nicely connected in a much tidier fashion than before, all for considerably less than the commercially available alternatives.

More soon …