[amsat-bb] Re: Winter Project

w4upd updwrb at bristor-assoc.com
Thu Jan 7 09:04:19 PST 2010

Not a problem when running them reduced power. 6146Bs worked well up to 
50mhz and at half power ran them up to 2 meters. 2C39 will easily work 
on 2 since I have used them to 1.2 and 2.3 ghz. However, they are harder 
to socket them. All of the tubes mentioned (and others) are available as 
new/old stock from various locations including RF Parts and Hamfests. I 
have also used 807Ws to two meters. However, 829B, 832, 5894A (used in 
the Johnson 6n2) work well and are available. Might put a request on QTH 
as a WTB for any of the above.

Again, as previously mentioned, old handbooks and old equipment manuals 
found on the various manual websites for free should give you good 
insite as to the schematics to build such a rig. I still have a lot of 
tubes here for the purpose of throwing something together once and a while.

Reid, W4UPD

Nigel Gunn G8IFF/W8IFF wrote:
> Things like 6146 struggle on 10M.
> You're expecting a lot getting it to go on 145MHz.
> QQV06-40 or 2C39 are better bets for VHF.
> On 07-Jan-10 16:28, wrb wrote:
>> I would try to locate old QSTs or Amateur Radio Handbooks that contained
>> such circuits. Tubes such as 6146, 829, etc. were good candidates. Also
>> the 4x/4CX150 would give up to 100+ out with just a few watts in. Newer
>> handbooks or magazines still provide you with he necessary theory to
>> build one from scratch. Building a tube amp is quite simple, just need
>> to have 300 - 1000 volts dc supply based on tube and power out. Also,
>> usually a 6.3vc transformer for filaments. Nothing wrong with tube amps.
>> I have an old Johnson 6n2 unit that runs about 150 watts. Neat old rig.
>> Find an old rig as I mentioned above and go online to the various manual
>> websites and obtain the manual for an old rig. You can use that as your
>> example.
>> Reid, W4UPD
>> Douglas Anoman wrote:
>>> I'm looking for a winter project can any one point me in the direction of a 2 meter tube amp nothing crazy about 25-50 out, 1-10 in. I have never used or played with a tube circuit so i thougt winter why not. Thanks 73
>>> Thank You
>>> Douglas Anoman
>>> KC9MLN
>>> Amsat #37043

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