2013 Maintenance and Upgrade Blog

Modified on 2014/01/01 13:18 by Administrator — Categorized as: Uncategorized




TO DO List

1/12

These are the two loading lines that were broken by the ice last year.

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The basic plan is to take the bottom 40m off the ring, tip it so the elements are vertical, then bring the broken ends of the two elements up to the tower by tilting the boom. To do that I plan to take at least one, maybe two come-a-longs up the tower to latch on to the boom on each side of the ring cradle. We’ll use the come-a-longs to do the heavy lifting and tilting, whoever is up there with me will be in charge of them. The biggest worry is that the ends of the elements stay away from the tower so they don’t get bent, and we don’t want anything to snag on guy wires, the ring, or the tower itself while we are tilting it. I have been looking at the loading rods with the telescope and they don’t look broken so I may just be able to put them back in the clamps and tighten them up, but if not I have spare rods. If anything looks weakened I’ll have some cable clamps to splice another piece in parallel. Once the two loading rods are fixed then we just set it down and put it back in the ring cradle.

N1TA came and helped and we pretty much did what I described above but without the come-a-longs... though it might have been good to have one of them to help tilt the boom.

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1/20 Had to free the pond end of the 160m V from a tall tree it got stuck in. Its a good thing the pond was frozen as I had to take the rope across it to get around a pine tree and move the end of it about 20' west to hopefully keep it out of that tree in the future.

1/23 Swapped the 160m FT-1000mp with the spare rig because the RX Antenna Jack is intermittent.

1/24 The North end Inverted-L for 160m broke at the feedpoint and is now blowing around in the 45mph wind gusts. Hopefully I'll be able to lasso it in the morning when the wind is supposed to be lighter so it can be fixed for the CQ 160m contest tomorrow night.

1/25 Fixed 160m Inverted-L... wind chill only -10f to -20f this morning, perfect day for antenna work!

1/26 Put rewound transformer in the broke HF-2500 and put it on 10m, seems ok. Resoldered circuit board connections on FT-1000mp with intermittent RX Antenna jack.

2/18 Bad weekend for amps... Friday night the 160m amp ptt keying became intermittent, or the grid protection is shutting it off. I ran it with no drive for an hour or two and the keying seemed consistent, so I suspect either tubes or the grid protection is doing something funky. I replaced it with the spare which had been the 10m amp before I put the rewound transformer one on there(see above). Then Saturday the 15m amp blew it's main fuse. That one appears to be the HV rectifier/filter as it still blew the fuse without any tubes, but didn't blow it when the HVAC from the transformer was disconnected. I replaced that one with the SO2R right hand station amp. Then later the one now on 160m started sounding like it had dirty relay contacts on receive, which could be a real problem as that one has the high speed relay board which meas the relays are a sealed type.

While I was at it I inventoried the Commander amps....


2/20 Took apart HF-2500 s/n 435 that was blowing fuses, don't see anything obvious in the power supply. There is some sign of heating but not the tracking from arcs in the board like what happened to s/n 698 in 2011. The diodes seem to be ok, as do the capacitors and bleeders, at least at ohm meter voltages.

For anyone who has ever wondered what the inside of an HF-2500 is like, here is the grand tour:

I take pictures like this whenever I am disassembling something this complicated just so I can go back when putting it together to make sure all the wires are routed properly and everything else is back where it belongs. Here is where I am starting. The top and bottom covers are off, the transformer is out from where it would be on the left side, and the tubes are out. This removes lots of the weight which makes it easier to handle and reach some of the hardware.

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Closeup of the front of the tuning cap and band switch:

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The back end of the tune cap and the high band coil and plate choke. Note the order of the stacking of the things connected to the closest terminal on the tune cap, if you get those backwards the small strap is too close to the sharp edge on the back support of the tune cap and it can arc.

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View under the plate choke. Older versions only had one capacitor on the HV power supply to ground on that short insulator(the one on the divider under the plate choke), but it was letting too much RF into the supply and metering so Pat supplied pairs of caps to replace the single one.

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Closeup of the back end of the band switch and how the strap from the band switch goes down to the load cap.

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Here the tune cap has been removed. To do that you take off the two wires from the band switch on the front, the high band coil and strap from the tube DC block caps on the back, then mark the shaft and knob alignment and loosen the two set screws in the knob bushing. Then there are two bolts through the center divider that are in slots that let you adjust it's position a bit. It is usually easier to remove the plate choke first, then take the nut off the back slot of the tune cap and back the bolt out of the nut that acts as a spacer so you can just slide the tune cap backwards off the front bolt and out of the knob bushing. The red tape on the RF out from the pi network wire is to remind me to keep it bent away from the back support of the load cap, another place it can arc if you put it together wrong. Note at this point, removing these from the divider is not really necessary just to get to the power supply, it just makes getting to the load cap easier. But it would be necessary to get to the low band toroid that is behind the load cap. Also notice the small black wire on the low band coil, this is an older coil which has had none of the melting problems seen on newer ones that use a larger gauge wire.(See melting pics) There are two possible explanations for this, one that the physically smaller wire leaves more room for air from the fan to move through the coil, the other is the higher resistance of the wire reduces the Q of the coil turns that are shorted when on 40m and 80m thus reducing the circulating current and heating. I must have broken the connection to the plate choke when I put in the new caps on that insulator as the choke is soldered to the HV lead from under the RF deck, I'll unsolder that and put it back on the lug that was there for it.

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Back view. On the left is an impedance transformer. On the right are the connections going to the power supply and filaments. The cable bundle to the right goes from the input network to the front of the band switch.

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Here I have loosened the set screw on the band switch shaft, I have also marked and loosened the screws on the load cap. Then underneath the chassis I removed the screws holding the RF deck and center divider down, and also the 3 screws holding the divider to the front panel. I then backed it off just enough to get the shafts out of the bushings.

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Here I have taped the row of connections together and taken them off the terminal strip and have pulled the RCA plug taking RF into the RF deck. Also I have removed the bundle of wires going alongside the RF deck to the front of the band switch out of their supports. At this point I could take a look under the deck but that is about as far up as it will go at this point.

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The final disconnect of the RF deck looks like this. I removed the white wire from the load cap to the transformer then removed the transformer and it's ground connection from the deck. And also disconnected the two leads for the fan from it's terminal strip. So now the RF deck can be removed and it exposes the power supply.

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As I am taking it apart I keep all the screws and other parts in these little plastic containers that electrical tape comes in. If I can't reassemble in a short time I put little notes in each container and put the lids on them so the parts are safely stored away.

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2/21 Dis-assembly was not really required... it was the transformer all along, this time instead of letting stinky smoke out it just shorted from the HV secondary to the primary. It didn't blow the fuse with BOTH of the secondary wires disconnected, but with only one of them disconnected it did... further measurements of resistance between windings proved the problem.

2/22 argh... dirty relay on HF-2500 s/n 720 is really bad. Put tubes from s/n 435 into s/n 765 to see if the tubes were what was causing keying problem, put s/n 765 back on 160m... keep fingers crossed.

2/23 Cleaned contacts on HF-2500 s/n 720 and put it on 15m for test, seems to be ok now. Had to cut off part of the top of the plastic housing to get at the contacts... just wrapping a paperclip around the Weller gun makes a nice hot knife for stuff like that.

2/24 Well, the tubes from HF-2500 s/n 435 ran all the way through the 160m contest in s/n 765, so most likely one of them is bad. Left those tubes in there on 160m. Now s/n 435 is waiting for a transformer and then will test those tubes, but likely one of them is bad when it heats up.

3/3 Well, the tubes from s/n 435 didn't fix s/n 765, it was shutting down last night. Apparently turning down the drive makes it work again. Something must be heating up in the control circuit and making the grid protection too sensitive or something like that. The s/n 435 tubes may be a bit soft also, the power seems to slowly drop as you keep it keyed. Swapped the tubes back again and the s/n 765 tubes don't lose power so that is not a problem with the power supply or something else.

3/9 First nice 'spring' day, only about 18" of snow on the ground, but sunny and only a light breeze. Went up the 10m tower and brought down the TIC 1022B Ring Rotor motor that was showing an open circuit.

3/10 Took apart the ring rotor motor, now its really broke, but is running for now. The problem appeared to be a stuck brush. I got it apart, but couldn't quite get it back together properly because of how the brush circuit board was held to the case. But it seems to be working anyway. I'll have to see if one of the other motors will work on that one or if there are replacements available from TIC.

3/18 Bought Commander HF-2500 s/n 503 from W2ID as another spare.

3/28 Got back transformer for HF-2500 s/n 435. Put in rewound transformer and fired up s/n 435. It didn't get up to full power, it seemed to be topped out at about 1000w on 10m. When not keyed the plate current was about 400ma, so something is wrong with the bias probably.

4/3 Still troubleshooting HF-2500 s/n 435... found 200ohm 10w resistor in series with diode between ground and B- on power supply board is open, but the diode seems ok. Schematic in book is not correct so that isn't helping much.

An easier way to get to the power supply is shown here. First remove the back panel, then disconnect the two capacitors and the bandswitch and the ground wire for the bandswitch from the front panel. Then remove the screws for the center divider from the front and bottom, and the RF deck screws from the bottom. The RF deck should then pull back from the front panel and tilt up from the back. This way you don't have to remove the wires from the rear terminal strip, though I did pull the RCA plug for RF into the deck to keep it from being flexed too much. A small box keeps the RF deck from falling over. In this condition everything except the ground wire that connects to the front of the RF deck under the bandswitch is still connected, so it should be possible to troubleshoot the power supply and it's connections.

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4/5 Found 80m 4-Square SWR high. Trudged down through the 6-12" of snow still on the ground and temporarily fixed the East vertical feed connection. Needs proper lug and re-waterproofing to finish up the job. Should check other feedpoints for fatigue also I guess.

4/7 Ok, now I'm making some progress... thanks for some of the tips from the amps reflector. Yesterday I traced out the circuits for the rf deck, hv power supply, and meter board, and was able to connect up the whole loop from B+ to B-, and it obviously didn't match the schematic that came with that amp... mainly the schematic showed a 8.2v 50w zener doing the biasing during tx and a grid leak resistor during rx that were switched by a relay... well, that relay existed but the terminals that should have switched the bias weren't hooked up. So today I was going to trace out the control and bias board which is up against the side frame of the inner case and partially blocked from view. So last night I dismounted it and got it so I could expose the whole thing so I could take pictures of the top and bottom to make tracing it out easier. This morning after another hint, and in looking at the board I found a label on it "QSK-1"... I don't have QSK in this amp and the old schematic had no reference to that. BUT, the circuit started looking familiar, and since I have several generations of those amps (8 of them in total from s/n 427 to s/n 765) I flipped through a couple of the newer books where I remembered seeing schematics for QSK boards and other variations. It appears that Pat started using newer boards but shipped some of the older amps without updating the schematics. So by s/n 427, bought in 1993, he had changed the control board in non-qsk amps to use the qsk bias and control board that is documented in later manuals. I have found one of the 400 series ones where he stuck in an updated schematic for the control board, but not all of them have that.... and that schematic isn't the same as the one I have, nor the same as is documented in a 700 series book. So this is progress... I went from having one bad schematic yesterday, to at least 4 different schematics this morning, one of which looks like the right one... and also comes with a board layout diagram that looks correct.

I disconnected the HV AC from the transformer to the plate supply, taped over exposed 120v stuff on the control board, shielded the AC on the back panel and powered up the control board. The supply voltages were ok and the startup delay was ok. But the bias and grid current measuring part of the board didn't work. So now I have some parts to order.

4/13 This is what 1/4" of ice at ground level can look like at 180'. These are of the ring rotor holding the 180' 40m4lldd showing the cables around the motor and boom brace and on the tower legs.

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4/14 Ok, hit a wall when trying to host video here, upload rate on DSL too slow... so started YouTube channel for stuff. Put up video from drone taking a look at the bottom 40m antenna.

4/20 Replace most of the components in the bias circuit for HF-2500 s/n 435. The plate current at idle just barely moves the needle now and the switching circuit does its job. The cutoff cathode voltage may be a bit low, but everything in the circuit checks out now.

4/21 Another advantage of having more than one of these… besides not being in a rush to fix it, is that I can put another one side by side and compare measurements. Yes, the cutoff bias is too low. A good amp was using about 45v in cutoff and 8.7 on tx. So back to troubleshooting… Found some more discrepancies in the board schematic and ended up tracing it back to the power supply board, which I had just sealed up because everything had tested ok on it. What I am seeing now is that the power supply is loading down the bias supply. The only connections to ground in the power supply are the multi-megohm divider for plate voltage, and a diode/resistor combo that is meant to protect against B- going negative with respect to the chassis… so the only possibility is that the diode is breaking down, even though it passed the standard ohm meter diode test feature. I can at least duplicate the problem by putting 12vdc on the B- wire that goes to the control board with it disconnected from the control board, with 12v it is drawing about 6-8ma which would be more than enough to drag down the bias supply that supplies 60v through 20kohms to supply the bias.

4/22 Well, 5 boxes that should be full of nice shiny 10m antennas got delivered today. Anyone want to help put them together??

4/28 Besides planting 10 dozen day lilies I did get HF-2500 s/n 435 repaired finally. The 1n5408 on the rf deck from B- to ground had turned itself into a 9v zener. So when the cathode bias was trying to shut the tube off it couldn't get the voltage high enough to do the job. I replaced that diode and the two on the meter board just to be safe and now it works just fine again.

5/17 Been busy with yard work, drone, cleaning crawlspace, building brass catcher, and lots of other stuff. Did have one thunderstorm with one lightning stroke, it appears to have taken out the NE/SW Beverage.

Good NE->SW (top trace pulsing NE, bottom trace receiving SW):

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Bad NE->SW:

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Good SW->NE:

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Bad SW->NE:

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Burnt off wire in shack end box:

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Halfway there, reflection isn't coming back properly so time to trek through the swamp:

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Can't see anything wrong with the reflection transformer, I'll have to compare resistances to good one later. But for now it is ready to go:

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5/18

Well, resistance readings on the bad reflection transformer are not definitive. All readings are a few tenths of an ohm, a bit lower than a new one but not that much different. So hook it up to the TDR. Put a pulse into either the + or - terminal and look at the other one. On the traces below the initial part where the top trace goes up is the pulse going into the coax which is about 25' long, after a delay it get reflected and the transformed result also comes out on the bottom trace through an identical length of coax.

Note on the good one pulsing into the + terminal the transitions are sharp and there is lots of ringing.

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But on the bad one the return on the lower trace is rounded and lower amplitude.

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On the good one pulsing the minus terminal the top trace shows a high impedance with a more rounded return.

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But on the bad one the upper trace shows a smaller impedance and the return on the lower trace is more rounded and lower amplitude.

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If you look at the original 'half fixed' traces you can see that the top trace shows a drop in impedance at the reflection transformer and a small return. Where the final fixed one has a rise in the impedance at the reflection and good size return. So most likely there is a short inside the windings of the core reducing it's effectiveness.

5/24 A mostly rainy and cool Friday. Made the coax for the new 10m stack. Each 70' of Davis RF RG-213 with Amphenol silver-teflon PL-259 on one end and a split end for the antenna feedpoint.

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5/25 This is what I get for starting a long weekend on Wednesday afternoon... Days of rain and cold, and now snow in the forecast for this afternoon! So what better to do than sit around sorting hardware for the new antennas. After looking at the assembly instructions and the single bag of hardware I decided to pre-assemble the boom-element clamps as that would use up about 3/4's of the nuts and bolts so I wouldn't have to sort them. So after assembling 25 boom-element clamps and sorting out the rest of the hardware this is what you end up with. After all that I came up missing the last 1/4-20 square nut for the last clamp. All the hardware bags looked intact, which is a very good thing, but i'll keep an eye on the boxes in case it got loose.

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Needless to say Pablo was not impressed...

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Then assemble the boom-mast and boom splice clamps:

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And put all the clamps on the booms, and you get 5 booms that are too big for the garage!

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6/1 Thanks to Tom W1TO for coming up to help assemble 10m antennas. With his help we turned 5 boxes of tubing and a pile of hose clamps into 50 element halves then mostly assembled one antenna.

Element halves:

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One antenna, all parts in place except feedline and not all aligned yet:

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6/7 Pablo's new friend.

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6/8 I didn't like how the feedpoint connection looked on the first one. Since the clamp ring doesn't go all the way around it looks like it could stretch or crack over time and loosen up. And with it out of reach on an installed antenna any fix later would be a real pain.

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So I simplified it a bit. Just to be sure the hole through the element didn't weaken it I tripled up the aluminum for the first 6" of the element. The new hardware is #8 ss salvaged from the 40m4LLDD stuff. I went with a longer screw so there would be plenty of room to put on another lock nut with some washers for the coax connection.

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6/15 Thanks to George who came over yesterday and today to help out all 5 of the new 10m Yagis are assembled and ready to raise.

6/30 George and W1IM showed up to help take down 4 of the old 10m Yagis, then N1TA showed up to take them apart and eat lunch.

Sure looks empty with only the top one left:

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One bucket for cold drink and to collect hardware, the other bucket for collecting tape.

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Empty Ring Rotor:

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On the ground:

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7/6 George, W1IM, N1TA, and W1TO were here bright and early to take down the top 10m antenna. It was just too windy by the time that was done to try putting up any of the new ones.

Getting it tied up:

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Bolts out:

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To get it past the first guy wire I tipped the back end down and rotated it around the tower.

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Then down it goes, but the wind and lack of room to the left because of the trees made it easier to just bring it down between the guy wires than to try to pull it out.

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On the ground. W1IM taking off the ropes. Notice the fiberglass rod tied/taped to the boom, that was to reinforce it after it was bent in the ice storm a couple years back.

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An empty tower at sunset...

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7/14 Got top two new 10m antennas up this morning. Had ground crew of N1TA(after being awake 24hrs for IARU contest), W1IM, and W1TO. Here are W1IM and N1TA waiting to rig up the second one to go up.

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Here I am finishing up the first one and moving the pulley.

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And then mounting the second one.

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7/19 Finished up the 10m stack this morning. Had big crew for a Friday morning... W1IM, W1TO, George, Tom (guest visiting neighbors), and just in time to finish up, N1QOV.

Ready to put one on the ring rotor.

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Taking 3 rolls of coax up to the switch box.

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The End.

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8/11 Did summer inspection tour of 150' tower. Tried to take a bit of the sag out of the top 20m antenna, had hard time because the turnbuckle is rusted too much to turn but think I got an inch or two anyway. Fixed side mount standoff on 120' 20m antenna so it should stay put now. Added or replaced a bunch of tape on cable runs.

8/17 Did inspection tour of 180' tower. Realigned top 40m rotor pot.

9/1 Replaced the 10m 120' and 15m 120' rotor control boxes with GreenHeron RT-21 controllers.

9/28 Went up 10m tower and taped everything down for winter. Took a few pictures from up there of the fall foliage.

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Mt Greylock is on the right end of the ridge behind the 150' tower:

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Not a good weekend for amps though. S/N 720 let out the magic smoke on first keyup on 15m Friday night. I opened it up and plugged it in Sunday and smoke came out of the top solid state power relay. S/N 443 blew its main fuse Sunday morning on 20m.

10/5 Replaced solid state relays in HF-2500 s/n 720, it seems to be working ok now. Took apart S/N 443, it is another transformer primary to secondary short. I think it also damaged the solid state relays as they are letting power through even when the front switch is off.

The solid state relays that turn on the HF-2500. They are tough to get in and out with the transformer in place but it is possible by removing a couple cable ties and pulling them out through the chassis cutout.

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10/11 Parts order came in from Digikey so I fixed the 12v 20a Astron supply for the VHF/UHF station so I could get rid of the noisy Kenwood switcher. Also did more troubleshooting on the 40m 4-square. Found a couple of ground connections that were intermittent from corrosion at the verticals. After that it still wasn't working properly so I pulled the box down... It must have taken a good lightning hit as the board was well fried and there was lots of soot blacking out all the relay covers. Ordered new one... starting mystery boxes for next year's NoBARC flea market early I guess.

10/16 Replaced Comtek box for 40m 4-square, now its working properly.

10/19 From odd symptom when testing HF2500 s/n 433 transformer I decided to test the solid state relays. One of them was bad also. This testing used a 240v dummy load made out of two 100w bulbs wired in series. It showed one of the relays was working but the other was always on. Fortunately I had saved the relays out of s/n 720 and the one that hadn't smoked tested out ok so I put that one in s/n 433. I also wired 120v directly to the control circuit power supply to test the fan and control board, everything there looks ok... the timer worked and the bias supply was producing the right voltages.

10/26 Another bad phono-phono cable on the 160m amp keying line???? Replaced it and the amp seemed to go back to keying reliably, again.

10/29 Installed the first 3 of the new Green Heron controllers to replace the TIC Ring controllers. Started with 40m bottom and both 20m rings.

10/30 Installed 2 more Green Heron controllers to replace the last two TIC Ring controllers.... here is the new look of the SO2R rotor and switch stacks. Note on the Yaesu rotors on the 180' 10m, 120' 10m, and 120' 15m, that I turned the knob 180 degrees so that North is up and South is down on all the boxes. I don't know if I'll leave them that way or not. Also the overlays to hide the dual bearing markings on the knobs are temporary until I get something that is nicely cut out and sticks properly.

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Just one more Green Heron box to install on the VHF/UHF station now.

10/31 Installed the VHF/UHF Green Heron box.

11/3 Nice cool autumn day... took chainsaw for a walk back to the SW/NE Beverage stream crossing and cut a bunch of downed stuff in the stream and new growth on the other side of the stream. Cleaned up some other stuff along the trails and around the 80m 4-square.

11/10 Walked around the Beverages and put back up a couple insulators knocked off by a branch coming down on the NW path.

11/13 Transformer for HF-2500 s/n 443 is back. Plug it in, big hum, blow fuse... that's not good. Disconnect stuff, get down to just primary, still does it.

11/14 Take transformer back out and do some tests on it. Putting 15vac on primary through 250 ohm resistor I can get output of 94vac, but only if I energize half the primary at a time. Going across whole primary gives nothing out. Email to TRS asking if I should try reversing one of the primary coils.

11/15 TRS says to try reversing one of the primary coils so I take apart two splices and swap the leads. Now it produces voltage on the secondary when energizing the whole primary, and the center tap has the proper 1/2 of the driving voltage. Put it in and test in the amp and it is running fine. I am guessing that maybe Commander changed color code on harness which resulted in swapping leads... but at least it is working now.

11/27 Replaced the ALC board in FT-1000mp s/n 9H460125, the VOX Gain pot was broken. Also vacuumed it out while I had it open. It also needed the 10W and 50W power levels adjusted, they were way too high. This one is at the 40m/SO2R-Left position.

11/29 Added a Green Heron wireless remote board to the 10m antenna switch controller. This allows remote control of the antenna selector from a computer using the Green Heron Everywhere wireless base.

Wired up to front panel switches:

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Stuffed in the box, just held by wires and spaced with cardboard front and back.

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11/30 Well, there were a few problems with connecting the GHE to the pushbuttons... besides being ugly it would give the possibility of the GHE Client software being out of sync with what the remote box relays were locked into. So I rewired it right into the diode matrix output. This will require a different method of locking out switching while the radio is keyed, but they say it can be done using the Wake line to make it sleep while keyed. It is now also wired into the power switch so the GHE Remote board is on when the pushbuttons are off and vice versa.

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12/13 Have tried 3 computers now, 2 tablets and now a desktop with a touchscreen, for use with the Green Heron Everywhere software. The best by far is an ASUS EEEBox with 21.5" Planar touchscreen monitor. It gives plenty of room for easy to see controls. The computer also mounts on the back of the monitor so it doesn't take up much desk space.

12/14 Wired up cables for audio from TS-2000's Acc-2 jack to the VHF computer for digital use, used a Pyle PHE300 Hum Destroyer to route audio from 2 radios to one stereo line-in jack. Also replaced the Rig Blaster that was breaking a ground loop from the VHF computer to the SO2R Mic In jack with a Pyle PHE300. Now the VHF station should be able to do FSK and PSK or any other digital mode much more easily.

12/21 Replaced RTTY left/right Y combiner on the SO2R computer with one of the Pyle PHE300s. Also put PHE300s in the audio from the computer to the RigBlaster on 10m/15m/20m/80m/160m. I think the 40m/SO2R is ok, but will check that when the contest is done... I had to order 2 more of them and more cables already because of the 2 that went for SO2R RTTY audio routing.

12/23 Made 3 cables to run WARC bands from hardline to SO2R station and stuck them up in the ceiling. Also made 3 coax chokes to feed the planned WARC Inverted Vs.

12/24 Ran 3 new cables outside from the SO2R station and connected to the 3 spare hardlines. Ran TDR and cable loss measurement with MFJ-269. Highest loss was 2.5db for the 350' of cable at 30MHz which was likely one of the two 1/2" lines, the best one was 1.5db which was probably the 5/8" one.

I am now the proud owner of 15000' (6x2500' reels) of IMSA Spec 28-3 insulated 10ga copper-weld wire. Anybody want some?? Only 91# per reel!

12/28 Made replacement hardline connector for the missing one on the 150' tower. Made up 3 center insulators for new Inverted-Vs from bullet proof plastic.

12/29 Rough cut the wires for the new Inverted-Vs.

12/30 Six 250' rolls of 1/4" black dacron showed up today. I also picked up some more split bolts. So now I should have all the parts to assemble and install them.

12/31 Assembled feedpoints for the 3 WARC Inverted V's.

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All 3 of them almost done.

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Closeup of feedpoint insulator. These are made out of bullet proof window material. I rounded the bottom corners to keep the edges from cutting the insulation on the copperweld.



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