[AMRadio] FW: Homebrew receiver

[manualman at juno.com]

I'll look for the list of 7360 electrically replaceable tubes. There
weren't that many, maybe 2 or 3. I seem to remember spending an entire
hamfest season several years ago searching for these replacements and
only finding a few. Never had a hum problem with the 7360's but component
values were very critical in order for the circuit to work properly.

Pete, WA2CWA

ps To All: Sorry for the earlier multiple posts. I didn't see my first
post go through, and rather than being patient, I resent  it two more
times in the course of 12 hours.

On Sat, 08 Nov 2003 20:26:27 +0000 "Donald Chester" <k4kyv at hotmail.com>
writes:
> 
> 
> There are several beam defection tubes in circulation during
> >the 60's time frame. Unfortunately, none of them are directly
> >interchangeable with each other unless one is willing to rewire 
> several
> >pins on the tube socket. Spec wise they are very close to each 
> other.
> 
> If anyone  has the data, maybe you  could post a list of all the 
> beam 
> deflection tubes of that era.  I think they were widely used in 
> tube-type 
> color TV's.   Sometimes the TV ones are cheaper than the 7360, but 
> on the 
> other hand, the cheap sweep tubes of the 60's now cost several times 
> more 
> than 6146B's.
> 
> One problem I  had with the 7360 was that the a.c. filament current 
> would 
> introduce hum into the circuit.  The magnetic field from the 
> filament would 
> modulate the beam deflection enough to modulate it slightly at 60~.  
> I am 
> sure this was never a problem with the  slopbucket rigs of that era 
> since 
> everything below about 500~ was rolled off anyway to produce 
> "communication 
> quality", but it was certainnly noticeable in my homebrew SSB 
> generator.  Of 
> course there is a very simple fix: use reasonalbly well filtered DC 
> on  the 
> filament.  I have found that to be necessary even with the 12AX7 1st 
> 
> amplifier stage of my mic preamp.

________________________________________________________________
The best thing to hit the internet in years - Juno SpeedBand!
Surf the web up to FIVE TIMES FASTER!
Only $14.95/ month - visit www.juno.com to sign up today!