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Rescued BC-610(I)
WB2FCN was minding his own "Radio Business", while suffering from the "FLU" when he saw on the List Server a cry to rescue yet another BC-610. It turns out Rich W5VDU wanted to sell a BC-610 he had gotten at an estate sale. Too many projects and no time, Jim saw this list posting and replied to Rich asking what the "deal" was on the "Beast". He said the first person to say I'll take it, gets it.Well Jim did and he asked when it had to be picked up, by next week was the answer as the auctioneer wanted to have the house cleaned out by then. So Jim and a friend packed up and drove over to bring it home. The unit had sat for quite a long time gathering dust and other residues of a household and looked pretty gross when he first saw it, but after taking a look inside Jim made a bet with Rich he could have it on the air in four days. Remember that he gets to it later. Took the skins off of the BC-610, and Jim carried the Antenna tuner BC-939-B and the Speech amplifier BC-614-E out to the station wagon. When Jim came back in this is what he saw.
Talk about your basic "Ugly Duckling" it looked like it had sat for a very long time. Most of the tubes were missing, there were "NO" usuable plug-in tuning units, and "NO" output coils. Hum well that is alright Jim can still put it on the "Air", just have to clean it up. There was about an eighth of an inch of dust on every horizontal surface and component. There was also some kind of liquid dripped on the R.F. deck around the PA tube socket.
Jim left to carry out the Antenna tuner and speech amplifier, while his friend "Loosened" the bolts on the Beast. He returned to find that the friend had "completely" removed the bolts on all three decks. Now boys and girls, don't try this at home, but Jim quickly told the friend to step back and away from the BC-610 and not to touch it! Lesson number one in disassembling a BC-610(I)
" NEVER TAKE ALL THE BOLTS OUT FIRST"!!! He explained to the friend that when you do that, the only thing keeping the decks in place is gravity. Yes, he knows they weigh a lot but if you bump any deck off the tiny rails it goes crashing down (gravity), and if there are tubes on the deck below, they get crushed, and the wiring harness to the decks gets "YANKED" out by the roots. So, first Jim took the harnesses off the decks one at a time starting with the R.F. deck, and removed the deck (lightest). Then he removed the harness from the modulator deck, and took it out. Now pay attention Ladies and Gentlemen, to remove (lift down) the Mod-Deck, center your body on the rear of the deck, reach forward with your
favored hand (the one you lift with) and grab the mod transformer on top. Slide the deck towards you until it is almost off the rails and then grab the bottom of the chassis with your other hand. Take one step backward, and lower the deck to the floor. Rest the deck up so you are looking under the chassis, this leans it on the transformers and caps mounted on the front of the chassis. Last you remove the harnesses from the HV deck, don't forget the two (2) leads going to the tune resistor. Then walk around to the front panel and face it, grab the top of the rails one hand on each side, and lift while taking one step backward. The HV deck will be in the clear and sitting on the floor, remove the four screws on each side of the front panel and the rails that hold the decks comes loose and that is how it is done. Dirty
Well Sunday gets there, and Jim tunes the transmitter in the full power mode and got 400 watts output into the dummy load, testing is fine but the "Real Test" is what does it do on the "Air"? So that afternoon Jim inserted his 7030 xtal, plugged in the plate coil ran a cable over to the BC-610 and answered "Doug AKA VO1CKX/VE3" on 7031.5 CW running 250 watts CW, then backed the power down to 150 watts (as minimal as it goes w/2.2 KV) and HE carried on a QSO for over an hour. Follows is the tube complement: 1) 250TH Eimac 190.00 2) 100TH Eimac 175.00 2) 3B28 13.00 2) 5Z3 19.00 2) 2A3 55.00 3) OD3/VR150 4.00 2) 807 RCA 15.00 1) 6L6G Metal 23.00 1) 6V6GT 11.00 These are the recommended tube replacements per the manual.
Final Result 1
Final Result 2
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