SimpleX Super Final! - Part 8

[@SpinStar1956]

JEEZZUSSS! Sat thru 8-parts of this, and not even a waterfall display--Man! In restoring old radios, one of the things I notice, is the better ones have nearly every circuit in its own shielded compartment. With the coils wound as solenoids, I'm sure there is a fair amount of interaction. The other thing that really surprised me, was the real need for shield-caps on most all the tubes. The one thing I notice is the really nice fidelity, including the low end from this receiver. So, hats of to you for doing this series; I really learned a lot of the unwritten lore. So thank you Mike for all the hard work and taking the excruciating time to document the build. 73...

[@MIKROWAVE1]

Oh it suffers from isolation issues all right! Hum Modulation etc... But it works pretty well for what it is and it is STABLE.

[@tennesseered586]

Bravo, Mike! The spirit of early radio lives on.

[@MIKROWAVE1]

It was fun to build.

[@mikesmuseum]

Your expertise really shined through on this project. Now we all know why 'voltage charts' are so important. That must be one incredible receiver! Excellent job Mike.

[@MIKROWAVE1]

This was a fun project but I think we learned how difficult in practice, building some of the "beginner" projects in the Handbook can be, even with your elmers expert help!

[@JCWise-sf9ww]

Surprising how a fairly simple circuit design for a radio receiver can perform so well. That would be one radio build to be proud of, Mike! 🙂👍📻

[@MIKROWAVE1]

I want to mate it with the Handbook 6DQ6 Transmitter to show a home built Novice station of 1959.

[@JCWise-sf9ww]

@@MIKROWAVE1 I see.

[@W1RMD]

Thanks a lot for sharing all of this with us. 73!

[@AdamosDad]

It has been a great project Mike; this is the radio hobby at its finest.

[@MIKROWAVE1]

Maybe time to get back to some solid state!

[@AdamosDad]

@@MIKROWAVE1 Anything you do in electrics will be solid work, sir

[@jerryuhte1284]

.Mike, congrats , probably a lot of builders were not happy with their build ! You found things to. be aware of ! Your troubleshooting g is just like some my earlier ones ! I have tried fixing a problem for days and find a bad test lead ! *hi) Your receiver is sounding great ! 73 K9UT

[@MIKROWAVE1]

Even a "simple" superheterodyne receiver like this is quite a step up in complexity and frustration from a 2 or 3 tube regen.

[@ornithopterindia]

👍Thank you sir.

[@JaakkoW]

Great Information ! Great Project!

[@mauriciosinigaglia4761]

Great job Mike, I have to say that nowadays there are few people who can successfully start and finish a project of this kind. I hope more colleagues venture into tube RF projects. I would like to suggest a theme for your next projects: An Phase Shift SSB exciter (generator) then a linear amplifier stage to increase the output power, for example, with two 807s forming a complete novice SSB station. Phase SHIFT can be anoying, but if weel assembled works beautiful. 73!

[@dbuckter8994]

@@mauriciosinigaglia4761 Great idea. Let’s hope Mike takes you up on it.

[@MIKROWAVE1]

Phasing rigs are very cool, and lots to learn there, I am sure.

[@dbuckter8994]

@ “Lots to learn” no doubt about that. and I have a selfish desire to see you tackle and share a SSB exciter project. BUT … to be a practical piece of gear a VFO would be another, necessary step, no? Thanks again for your inspiring work. W6BOW

[@nigelbrockwell6237]

A great project with a lot of potential. Thanks for sharing its secrets with us.

[@MIKROWAVE1]

Those 1950s hams were very clever with tubes to wrangle out a lot of performance with few parts.

[@Steve-GM0HUU]

I would say it has high potential 😂.

[@MIKROWAVE1]

@Steve-GM0HUU only one shock whole project. I accidently touched an exposed resistor lead that was not covered with tubing.

[@NebukedNezzer]

all is well that ends well. I bought a 1945 Scott low radiation marine LRM receiver that was a shop dog. the previous people used it by putting a wire to the grid cap of the 6k7 rf amp(bypassing the front end). In trouble shooting I found a crum of copper in the band switch that shorted it out. took a dental pick and removed it and wa la it works great. I am a professional electronics tech and have found all kinds of defects in construction. one common thing is solder chaff from flow soldering boards getting all over the pc board. knock it on the bench and wa la. anything can go wrong and will go wrong at the most inconvenient time. loved this build.

[@MIKROWAVE1]

Shop dogs of all kinds can come with factory errors. I have found working command receivers with wire wrapped around a post and no solder!

[@dbuckter8994]

Awesome! Your patience has been rewarded. It sounds great. Warm, rich, and full. Like my old SX-99 but even better. Tubes (valves) rule? Thanks for sharing. 73 de W6BOW

[@MIKROWAVE1]

It's hard to beat audio in those old premium receivers like the Hallicrafters and the SuperPros. Some of these even had a phono input! The simple class A triode output is pretty primitive in this, but it sound pretty sweet.

[@Steve-GM0HUU]

👍Nice you found the mixer mystery Mike. Certainly sounds nice and perky now. Maybe goes to show the value of doing the voltage chart. As well as flagging up voltages that aren't quite right, can be useful for quick fault finding later on.

[@MIKROWAVE1]

I finally bit the bullet and went with grounded heaters with mini coax line like the book says. Not seeing much improvement compared to twisted with the hum pot and really did not expect much. There is something going on with hum at high volume.

[@Broken_Yugo]

IME melting wire insulation while soldering is usually down to too much time on the joint, something is wrong if it's not wetting out fast, usually the fault of one or two things. The iron isn't hot/heavy enough to heat things quickly enough, more tip mass and the shortest path to the heater is more better, the better you can dump heat in a local area the less time it has to wick outward. Or the flux isn't aggressive enough to chew down to metal and wet out quickly. Pre flux everything with just a dab of a good cleaning optional RA flux from a reputable brand and the problems tend to go away, sometimes I'll brush the solder wire with it too, liquid or paste is more economical than the pens.

[@MIKROWAVE1]

Yes Yes and Yes. I wish I was a pro solder slinger!

[@Capecodham]

You are the master. I will buy it.

[@MIKROWAVE1]

No! You will just put those fancy knobs on it.

[@Capecodham]

@@MIKROWAVE1 No yours is perfect.

[@mackfisher4487]

Mike, You added to your prestige in my book when you offer to support your subscribers.

[@MIKROWAVE1]

Thanks for watching! And the Patreon Channel is evolving into a valuable resource for sharing project progress and roadblocks.

[@californiakayaker]

I'm one of the few that has actually lived through part of the era of tubes. I've even built a tube controlled voltage regulator. Remember the different colors for different voltages ? N6GRG (Photo is from a crazy movie called Captain Ron, it isn't me).

[@MIKROWAVE1]

Those series tube regulators with 6L6's and 6AQ5's with a 6SG7 or 6BA6 control tube and a VR reference work very well.

[@MIKROWAVE1]

Slight error at 11:00. I neglected to load the initial 77 mV RMS level with 50 Ohms at the meter. The sensitivity is actually a bit better than shown.

[@JuhaK71]

Hello again! Nice to hear it is working! My receiver has now all the main parts installed, I have just to start the wiring. How your receiver can manage very strong signals? Can the regen pot reduce the gain much enough to perevent the oveload? Perhaps the front end circuit can be used to limit too strong signals, that is what I have to do with my Hammarlund HQ-100 on the 80m band.

[@MIKROWAVE1]

Actually the dynamic range is not bad on the top end. It certainly would benefit from an RF stage with audio derived AGC.

[@MIKROWAVE1]

And Congratulations on taking on the project!

[@JuhaK71]

​@@MIKROWAVE1Thank you!

[@paulphoad]

What an incredible difference!! Makes you wonder why regen in later receivers was abandoned. I suppose extra IF stages got cheaper... good work

[@MIKROWAVE1]

AGC is much easier to accomplish with superhets. I find that on 40m it is annoying when the band is fading rapidly with such a simple circuit.

[@paulphoad]

@MIKROWAVE1 of course, AGC!! I didn't think of that. Maybe that's the next mod. Rectify the IF (-ve) and feed back to earlier stages..could it be done with just some genuine "period" germanium diodes. Or just get very good at turning the rf gain (regen in this case) control up and down and up and down 😆

[@kazcat8096]

Hi its good to see you got it all working i have got to the stage of power supply all working and audio amplifier done and working i will keep flicking back to your videos for tips when you have yours on 5mhz wwv can you tune up the band for 60m band

[@MIKROWAVE1]

Not quite because of the added capacitance. I can hit 5.2 MHz.

[@MIKROWAVE1]

But you could easily employ the 6th position and tune 60M nicely with a separate trimmer. You just cant quite do it on the WWV band 5.

[@kazcat8096]

@@MIKROWAVE1 thanks i will do that once i get mine fully working

[@timhutchison-l7o]

What about some help with the 2 tube amp. Sounds comes thought it to the speaker but no amplification. Volume control works.

[@MIKROWAVE1]

Tim, which amplifier? The 6CG7 one in this or another circuit?

[@donaldhutchison2089]

@@MIKROWAVE1 the one with 1u5 and 3v4 tubes

[@MIKROWAVE1]

@@donaldhutchison2089 I have that amplifier and will take some measurements for you.

[@donaldhutchison2089]

@@MIKROWAVE1 i checked the neg. voltage to pin 6 (neg.) and pin 1(pos) of 3v4, should be -1.2, i have -0.6 volts . but if i bypass the r4 1M resistor its -2.4 volts. the other resistors are R1 50k, R2 10M, R3 1M, R4 1M, R5 470 (yellow, violet , brown)

[@donaldhutchison2089]

i got the voltage up to -1.2 volts, still no improvement

[@rtybn2012]

i have ordered the following items, litz wire 10/44 200ft, 4x2Mhz series resonance crystals and bought on ebay some if xmfr so I can rewind coils for the rf osc. crystal filter and grid leak detector. Question-what type of wire did you use for the input filter, L1 and L3.

[@MIKROWAVE1]

I used old thin telephone wire. Solid with PVC.

[@metatechnologist]

Lot's of hard work here. I understand you're pretty tired of it at this point. But I'd be interested in seeing the RF Amp version of this.

[@MIKROWAVE1]

With a normal open band it is solid. I have been making contacts on it and can also report that the sidetone mute feature is shockingly excellent, but yes, when the band is weak, you could use some extra gain and I am tempted to use the regen - which pops everything up.

[@rtybn2012]

Do you do anything on 2 meters?

[@carl-gunnarhillefors7612]

GOOD WORK AND CONSTRUCTION! NEARLY AS SIMPLE A "PARASET" - THE WWII SPYRX/TX 0,5-1WATT WITH JUST RANDOM ANTENNA! GOOD WORK AND SIMPLICITY! 73s de Gunnar sm6oer >>\

[@MIKROWAVE1]

The Paraset build for me was 1/3 frustration in collecting the parts, 1/3 making the case and metal work, and 1/3 The tightness of the build. The circuit itself was solid; and the performance was and continues to be stellar.