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I think my BM adjustment was inadvertently changed when adjusting the ALC.? They are next to each other.? I couldn't find anything about this adjustment in the user or repair manuals.? Can any help me make sure the BM adjustment is set correctly?

On a different topic.? I have an FT-101B that I used back in the 70s.? It has been sitting in a box for maybe 40 years.? I started it up using a variac and bringing the voltage up slowly.? It is clear from noise in various controls and switches that there are dirty of corroded contacts.? Is it advisable to spray contact cleaner on noise controls and, if so, what is the correct way to do this?

It does send and receive.

I look forward to and appreciate any assistance on these two matters.

Thanks,

--Kenoli
KB6EMG

Thanks.? I have that manual however and it says nothing about a bm adjustment.

--Kenoli

Hi Kenoli,
Sorry no one has got back to you until now.

RE your BM adjustment: If you have another radio with a receiver use this procedure. Tune up the radio you want to adjust on one of the lower bands (80, 40 or 20) into a dummy load. Switch it to USB or LSB and listen to it with the second receiver. Then turn the mike gain all the way down and adjust the control right next to the ALC pot a bit off center until you can hear the carrier clearly on the second receiver. You may have to tune the second receiver off frequency a bit to hear the carrier as a tone. Then adjust the POT for the lowest carrier signal. You may also see the IC meter go up and down a bit.

RE your 40 year old FT-101B high voltage capacitors. You should replace the two main high voltage capacitors on a 40+ year old FT-101. See eBay item https://www.ebay.com/itm/254527364032?hash=item3b43035bc0:g:CDoAAOSwyWheWysT (I have nothing to do with the seller). If they fail they can take out the power transformer.

It's also a good idea to change out C13, the 80pf@ 1kv driver to final coupling capacitor.? Also C11 a 200pf @ 1kv in the driver plate circuit? Bad things can happen if C13 shorts.

RE scratchy controls and switches. The first thing I do with a radio that has been stored for a long time is exercise all of the front switches (especially the band switch) and pots end to end. Sometimes as high as 40 times each with the power off. Then I check to see what is still noisy and go from there. Most people like the Deoxit brand for cleaning switches and pots. Use care on the band switch - I use a toothpick and apply only to the contacts.

73
Roger VE7LB Group Owner

Hi again Kenoli,
I also could not find the Carrier Balance procedure in the Service Manual I have on hand. I did find a better SM copy and have uploaded it to our FILES section here.
Look for CARRIER BALANCE on page 7-10 (Adobe page 184) of the FT-101 Service Manual Best Copy OCR that I just uploaded.

Thanks to Emerson PP6EW for the heads-up on the better SM.

73
Roger VE7LB