[Boatanchors] Mixer Troubleshooting Question For my Homebrew Superhet Novice Receiver

[wa9wfa]

Hi Dave, Thanks for the story about your Mate for the Mighty Midget Receiver project back when you were a kid.  Too bad the project was a disappointment because there is a lot of construction work involved to find out if it works decently or not.  Still, you have fond memories of you and your Dad working on it after you built it.  In 66 I was 13 also but this project was way beyond my ability and I didn’t have any electronic help.  Do you still have it?  Maybe there’s a chance you could get it working now.  

Frankly I don’t know what to expect for performance.  I saw one on YouTube but the fellow had hot rodded it quite a bit with AGC, additional audio and IF stages, filtering.  As I was laying out this receiver I was sorely tempted to add an additional IF amplifier stage, mechanical filter, better coil tuning with variable caps, additional audio stage, but then it wouldn’t be the Mate for the Mighty Midget any more, so I kept it pretty much original with the exception of moving the power transformer out of the box.   The cabinet front panel is nearly identical and the chassis layout is very similar.  

Lew McCoy must have been a master builder because it’s a challenge to cram all those parts into that tiny chassis.  I always thought it was too complicated for the  Beginner and Novice section, at least for us young kids anyway.

Thanks for the good luck.  It arrived this morning.  So far the RF amp is working, HF oscillator working but on the wrong frequency, mixer working now that I figured out the test measurement problem.  Now I’ll fix the HF oscillator frequency so I can have a 453 KHz IF instead of the current 745 KHz IF, then proceed with testing the crystal filter circuit then product detector then audio.  

As for the April fool issues of QST, what great fun that was reading through the article and trying to pick out the bogus technical articles.  Sometimes it wasn’t so obvious :)

73, Scott WA9WFA



> On Feb 26, 2021, at 8:55 AM, Dave Hollander <n7rk at cox.net> wrote:
> 
> Hi Scott - I built that receiver in 1966 when I was 13. My dad bought me all the parts at Henry Radio. I punched the chassis, assembled and wired it. Could not get it to work so asked my dad to help. He was an engineer at Collins Radio in Newport Beach, California at that time and not yet a ham. He spent quite a few hours on it and got it going but it never worked right. The whole project was a big disapointment for both of us. Don't recall any more details. Maybe it was an April Fools article :-)
> 
> Good luck,
> 
> Dave N7RK (ex-WB6NRK)
> 
> 
> -- 
> Dave Hollander N7RK
> Arizona Tube Supply
> http://arizonatubesupply.com
> 
> Ham Radio Page
> http://n7rk.com