[AMRadio] RE: homebrew receiver progress

[Brett Gazdzinski]

Hello all AM,ers.
I have been making great progress on the second homebrew superhet
receiver.
I have the chassis all punched out, holes drilled, and primed and painted
light gray to match the push pull transmitter.
Front panel is drilled and painted black.
Last night I mounted the transformers, chokes, tube sockets, IF cans,
bfo crystal, terminal strips, filter board, lo coil and switch box,
and output jacks for audio, mute, IF output (for scope), antenna hookup.

I have to add the handles to the front panel, paint the side supports,
then I can center and mount the tuning cap and preselector cap, install
the controls and switches.

I also forgot to drill holes for the s meter sensitivity and zero pots.

I have a nice heathkit S meter, and will use 3 ultra bright red led's
to light the meter up. I tested it, and it looks cool.

The digital display is built and tested.

Wiring the power supply will be first, once I have the HV,
I can wire and test the LO, then the mixer, then the filter setup,
then one IF amp at a time, and so on.

So far, it looks very good! No extra holes from changes like
the first homebrew, hope it stays that way!

I am already thinking about the next project, a homebrew AM transceiver.
Something running a pair of 6146 tubes, or a 4d32 (I have lots of those),
simple superhet, all in a small package as possible, say dx100/32v3 size.
Maybe just 40 meters, since 100 watts wont do on 80 very often.
That will also make the design simple, no band switching.
It should be really fun, putting both receiver and transmitter
in a small package, and integrating both systems together.

I am not sure if a stable homebrew vfo will be possible, I may have to go
with one of the VFO kits that are available, digital frequency
display, pair of KT88 mod tubes.

That should keep me busy for quite some time, but sure would be
fun to build and operate!
 
I have been all fired up on ham radio and building lately!
 

Brett
N2DTS

RE: [AMRadio] RE: homebrew receiver progress

[Brett Gazdzinski]

Eddy,
I do have some Bill Orr handbooks, good stuff in there.

I built the power supplies, both the high voltage and low voltage
and wired up all the filaments on the homebrew receiver tonight.
Still some work to do on the power, I need to get a low voltage 
for the frequency display backlight and S meter led's.

A really stable homebrew vfo might be hard for me.
The LO in the receiver is ok, once it warms up, so maybe
it can be done.

There used to be a company that made a kit, a DDS vfo, with memories
and so on, which would be cool, but I cant find it anymore, I think it was 
S+S who sold it.
Tubes and caps are more fun anyway.

Brett
N2DTS
 
 
 Hi Brett...
 
 Just goes to show you can't keep a good man down! Hi Hi You sure are a
 prolific builder!
 
 If you have any of the old Bill Orr RADIO HANDBOOKs from the 
 1950's, Brett,
 he featured neat mono-band AM transceivers therein---I recall (was it
 the '58 edition..?) he had a neat 10-meter design, but it was 
 strictly low
 power. Still a nice package, though,  on 10 who needs QRO anyway...?
 
 Building a stable, homebrew VFO is NOT an impossible 
 task---in fact, there
 was an excellent piece by Walt Hutchens in an older ELECTRIC 
 RADIO magazine
 that tackled this very project.
 
 A few months back I built a HB VFO for 40-meters that used NO SOLID
 DIELECTRIC CAPACITORS WHATEVER---everything was air 
 dielectric. Even the
 coil was an air core BW miniductor! This I did to try  
 eliminate/minimize
 drift over time without worry about NPO caps, etc. etc.
 
 It worked, too, in the short run---really stable for the 
 first two hours,
 or so, but then it started to drift ever so slowly. Anyway, 
 it was a fun
 experiment...
 
 Good luck with yours!
 
 ~73!~ Eddy VE3CUI - VE3XZ