For the 0A2 replacement...might want to check this out.. http://www.solidstatetubes.com/0a2-and-0b2.html
Thanks..Rich N7TR Rich N7TR ex KI3V, N3AMK, WB3JOV www.n7tr.com<http://www.n7tr.com> http://www.qrz.com/db/N7TR Telnet: dxc.n7tr.com N7TR DXCluster -----Original Message----- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Charlie Cunningham Sent: Friday, December 20, 2013 9:21 PM To: 'Bill Cromwell' Cc: 'top Band' Subject: Re: Topband: DX-100 adventure - progress Hi, Bill! That's great! You're good to go with the elecrolytics, then! BTW - as for the chirp on the signal - the DX-100 VFO and voltage regulator was pretty much what they sold separately as the VF-1 vfo. The DX-40 had a socket to power it, but I never could get rid of the chirp, until I built a separate PS for the VFO. The OA2 gas tube just wasn't stiff enough to eliminate the chirp. You might be able to eliminate most of the chirp by replacing the gas tube with a Zener Diode. By the time you get up ro a 100 volts with the Zener, it's really avalanche breakdown and has a pretty stiff knee. Might improve your chirp! Have Fun! 73, Charlie, K4OTV -----Original Message----- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bill Cromwell Sent: Friday, December 20, 2013 11:12 PM To: Charlie Cunningham Cc: 'top Band' Subject: Re: Topband: DX-100 adventure - progress On 12/20/2013 11:00 PM, Charlie Cunningham wrote: > BTW, Biii - tip/suggestion - for those series-connected electrolytics > you probably should put a pair of equal value resistors - one across > each series > capacitor, as the leakage currents will not be equal in each capacitor > in each series string and the DC voltage won't divide equally across > each capacitor unless you put individual "bleeder" or "swamping" > resistors across > each cap in the series pair to equalize the DC across each capacitor > in the > series! I'll be interested to see how it turns out! I never had a > DX-100 "Benton Harbor Kilowatt"! I did have a DX-40 for a while, but > no 160 on that one, though! I do have an EF Johnson Navigator in > pretty good condition > that needs to have all of its electrolytics replaced because of their age. > I does have 160 (and 11 meters also!). > > Good luck and Merry Christmas! > > 73, > Charlie, K4OTV > > Hi Charlie, In the DX-100 there is already a big honking pair of bleeder resistors so that the bleeder is divided with one half across each half of the series pair. I think that's what you meant. The DX-100 originally had two caps rated at 450 volts in series and the bleeder set up that way. 73, Bill KU8H _________________ Topband Reflector Archives - http://www.contesting.com/_topband _________________ Topband Reflector Archives - http://www.contesting.com/_topband _________________ Topband Reflector Archives - http://www.contesting.com/_topband