[Boatanchors] outboard power supply for EF Johnson VFO 122

[brianpepperdine brianpepperdine]

OK that probably gives on good reason... stable power to avoid the CW chip.
Excellent!
Yes, as a project it seems fine, even from scratch. I just got the schematic of
Terry's D Labs project from him and the p/s portion seems straightforward, which
will help me out whether I build from scratch or use the Heath or EFJ chassic
components I seem to have on hand.
Yes, when running my Valiant II this winter (first season with that) if I didn't
have it warm up or enough time to operate before it stabilized the drifting
(which was not all that much over time IMHO) had the stations with modern
bandpass just have me fade to obscurity on their end! Nothing new about that in
the olde daze, but now.....

Projects are a long list here, aside from messing with re-birthing radios I have
a home to renovate post-retirement - skills I have and skills I will have to
acquire (which is fun though sometimes daunting).
73 es tnx
Brian VE3HI


> ---------- Original Message ----------
> From: Rob Atkinson <ranchorobbo at gmail.com>
> Date: April 25, 2021 at 3:28 PM
> 
> 
> It's not too hard to build a small supply for a 122 and this is a
> great starter project for homebrewing.   It just needs to supply
> around 100 ma (to run cool for long periods) 250 v. DC and 6.3 v. AC.
> 1 amp for the filaments is probably more than enough.  There are two
> advantages:  You can power the VFO separately and leave it on to avoid
> warm up drift when you operate.  I usually power mine up an hour
> before I fire everything else up and I used to leave it on all weekend
> when I was working before I retired.  You can't do that with a rig
> that has a VFO built in or running of the rig's supply unless you like
> having your DX100 sit there all on all day.   This also allows you to
> run more than one rig with the 122 if you want to.  Powering the VFO
> off the rig is fine...for AM.  On CW, it might get chirpy without
> being on its own separate supply, but a lot depends on how it is
> keyed.  CW chirp from the VFO can be avoided by letting it free-run on
> CW.
> 
> 
> 73
> 
> Rob
> K5UJ