The AM Forum

About 6 months ago I was looking at the junkbox, which is about half of the basement, and wondered if I had enough stuff to build a small receiver.  After some figuring on paper, thought I probably did, so dug through some 50's and 60' handbooks and articles and put some schematics on paper.  Since I was using what was on hand, obviously had to make some changes as I went along.  80 M RF deck is done and aligned.  IF deck is from a ARC-38A aircraft radio [250 kc] with Collins filters.  Audio deck works OK after replacing the questionable output transformer.  Tube lineup is 6BA6 RF amp, 6BE6 mixer, 6C4 local oscillator for 80 M RF deck and 6C4 driving 6AQ5 audio amp.  Got tired of using a VTVM for aligning, so added a 6C4 tuning meter deck using an old 5 ma meter.  All the metal work is homebrew using mostly aluminum angle and C-channel and street sign aluminum.  Plan now is to keep adding converters as I have the time using the 80 M RF deck as a first IF. A work slowly in progress.

What suprised me is that the stability after about 15 minute warm-up is equivalent to my 75S-1; much better than my Hammarland and Halllicrafters rigs.

Pictures are not the best, but best the camera will do.

I love the no parking sign as part of the chassis :D

Great job!

Sometimes it is just fun to do a project like that. the challenge of using what you have laying around WITHOUT buying any parts is the fun of it!!

My PW 75 meter "piss weaker" was one of those projects. The main rule of the project was that EVERYTHING had to be recycled from something else. NO NEW PARTS!!

The cabinet was recycled from something else and I stretched a piece of aluminum flashing across the face to give me new spots to drill holes, the power transformer came from a junked receiver, the mod tranny was a push-pull audio outpoot tranny.
and the final configuration ended up being a 2E26 modded by a single 6V6. It ended up working very well and was a fun project.

Kudos! :D

73DG

Cool people build receivers

Hot people build transmitters :D

73DG

Mitch,

Congratulations on taking on a project which dates back to how things were normally done years ago in our hobby.  When money was tight, especially in the 20's and 30's that was quite the norm. 

That is why I view my junk box with more value to me than all the commercial vintage gear I have.  Plus, its just darn fun to create something yourself. 
Personally, I get buzzed out with to much restoration work where your just mainly changing resistors and capacitors out.  Its nice to roll your own gear so to speak. 

Now that you have a rcvr up and running how about a transmitter to go along with it? 

Continue the journey OM.....

Joe, W3GMS

Bigger pictures would be nice.  Those are thumbnail size

Street signs were the preferred material for floorboards and homebrew back in the good old days. ::)
Two workers and a driver could remove a sign and be gone in well under a minute ;D

Carl

Wicked Cool Mitch and junkbox receivers are real learning tools.starting with the ARC-38 IF is a great idea and that gets a big difficult chunk done right and playing out of the box. Now you strap on some audio and a 6BE6 and suddenly you have a receiver. Next you turn that into the second conversion and add a front end and AGC and BINGO!

Mike WU2D

one way signage for the floor boards... easy to 'break'.


klc

I ran downstairs and took some pix of the 5w Piss weaker.

Clarkie, tell me this is Hammy Hamboned!!

Dont talk the talk unless you can walk the walk  ;D  ;D

Here is one more for good luck.

The carpenters rule in the first pix is to give one an idea of it's size.

Oh, yea it is also full push to talk and has the antenna switching and receiver muting contacts built in.

Size is impressive - remember the gear with the big slide rule dials? It takes a while to get across the front of my Marauder to the high end of the band. Who has tackled a dial string setup on a homebrew?

Nice job on the receiver!


If the bullet holes are just in the right places, saves you from drilling holes. I guess they are best harvested in a city?

Nice job Frank. I have that same exact style cabinet and have a PS for an AF 67 built into it. I bought the cabinet new but I forgot where?

Thanks, Terry

Besides the theme of "no new parts", It was actually built for a purpose.
I built it to be a low powered exciter for my Junkston T-Bolt.

Some answers and comments:

Have considered building a xmtr.  Have enough stuff to build a 70 W AM rig.  Would like to build a 3 or 4 811 rig, but xfmr stock won't support it right now.  Local hamfest coming up again in November, so that may change.

Know what you mean about restoring existing equipment.  Even the green radios mostly look the same inside.

I think the real fun of this project was getting out the calculator, since the slide rule is too fuzzy in the brain, and doing the math to make variable caps on hand tune where I needed.  PVC pipe makes fine coil forms.  Let's face it, there are only so many ways to build an oscillator, mixer, or amp.

The hardest part was the metal work.  Mostly done with hand tools; only expection is drill press.  The main dial took some design work, but making it was just time consuming.

Thanks all for the comments.

Great Job!