B&W 5100B

[N6WDR]

I just bought a B&W 5100B today and pick it up tomorrow.  I was wondering if anyone knows of any mods that can be done to this radio, I am really looking for audio mods.

Thanks,
Richard N6WDR

[Jim, W5JO]

Pull the audio subchassis off and look to see if the couplate has been removed.  If not, you can do that and replace the coupling cap with a larger one to broaden the audio bandwidth.

Get an RCA receiving tube manual or older ARRL handbook and follow the diagram suggestions on the audio tubes.  The power supply in the B model is a bit light so you should take that into consideration when operating.

[N6WDR]

Jim, Thanks for the suggestion, I will look at it today when I pick it up and throw it up on the bench.  When you say light power supply, how light? in other words comparable to my valiant power supply or worse?

Richard N6WDR

[Jim, W5JO]

Not a lot of difference between the power supplies.  You will find the B model has a bit of trouble getting to 100% positive.  100% negative is easy.  Be sure to replace all the paper caps when inside, plus the electrolytics.

All this is predicated on the fact noting has been done to it.  If you find tracks of someone changing anything, then document those changes first to see what has been done.  Another thing you can do is pull the diagram of the 5100 audio chassis and use those discreet component values to mode the B.

It does pretty good audio anyway, but it can be a bit better.

[N3DRB The Derb]

hi res digital camera is yer buddy. take hi res ( >3MP) of the underside.

[N6WDR]

Thank You for all the info  , I didn't pick it up last night, so tonite will be the night I get to open her up and see what she looks like inside. I will go through it with a fine tooth comb and see what I come up with.

Thanks Again,

Richard N6WDR