Ferrite and Frame Loop Regens

Let's add Regeneration to our Grid Leak Detectors that are made for indoor use with both Ferrite and Frame Loop Antennas.

[@clytle374]

Interesting to see this old receivers built and function. Educational as always. Regen amuses me, just short of being an oscillator, and sometimes is an oscillator.

[@MIKROWAVE1]

There was a big fight as to who exactly invented regeneration. The real winner was the person who figured out how to keep these circuits FROM OSCILLATING!

[@johnwest7993]

I've built a couple of TRF radios, one for WWVB, and one for 1750 meters to monitor my LowFer beacon. I like them for their simplicity for low frequency applications, (and for not having any intermediate frequency conversion,) and for dedicated, single channel, low frequency applications. They use very few components, are almost impossible to screw up, other than from unintended feedback, and are ridiculously easy to tune up and troubleshoot. You can build them with 2, 3, 4 or more identical resonant gain stages depending on your application. Just carefully isolate the stages from one-another, ground the coax, (I haven't used any other type of transmission line,) and ground the receiver. Put it in a metal enclosure, and put the antenna well away from the receiver because the antenna can detect the amplified signal in the receiver from a surprising distance away and cause feedback.

[@MIKROWAVE1]

TRF works great at low frequencies where you can get a lot of selectivity and gain without stability issues. I made my Lowfer receiver with a single upconversion to a crystal ladder filter at 4 MHz.

[@JCWise-sf9ww]

I really enjoy these videos on the simple AM receivers. This is a real education on the variations of early AM radio receivers. Boy scout stuff.

[@MIKROWAVE1]

I have a Bot Scout Merit Bade book called RADIO from the 1970's that has a full superheterodyne Ham Receiver project in it!

[@ka4dqe606]

Great stuff ... lots of useful bits on your channel. The capacitance reminder for the loop antenna is appreciated. Cheers

[@vacuumfireradio253]

Looking forward to the next one as always. Thanks Mike.

[@tomstrum6259]

This tube Regen with a similar size Frame Loop antenna work well & Tunes really Smooth....Made a few Mods to use a Single 12 vot Battery fillament & Plate supply....I substituted the 1625 (Ww2 1942 era) Pentode for both stages & Added a 3rd audio Amp stage....Everything on a pine Board, the 3 big bright Glowing plate Cap 1625 "Fire Bottle" tubes Never fail to Impress everyone with the old "Vintage" look....The High fillament Current Cathodes must be "Boiling" those Electron off for the 12 volt Plate & screen to Work so well !!....Thx for sharing your Fine working easy to Mod regen project

[@MIKROWAVE1]

My two best regens are both tube types; one is a classic Armstrong triode pair on 80M and the other is a Hartley with a pentode driving a triode audio stage on 40M. They both have lift link coupling and are single band Vernier-driven and are in tight metal chassis. They keep up with my R390A easily on the bands that they are designed for. But the all band and low voltage hobby regens are where the real fun is for most folks.

[@akdenyer]

Just wonderful. Wish I had somebody like you nearer I could learn so much. It takes time to gain so much experience.

[@MIKROWAVE1]

Thanks for watching!

[@SteveHacker]

I really want to start building radios like this with my son, but don’t even know where to begin. I’d for sure need the “For Dummies” version of step-by-step instructions…

[@user-bo8eq7ki5w]

FRAME ( old antenna for medium wawe) its Power ! )))

[@freda5344]

How long do those 9V Bat cells last? They are actually quite expensive here (esp relative to any other cell types you could buy, it would be cheaper buying a bulk pack of 1.5V cells and you get a much bigger capacity along with that). I wonder how it would go with a 12V bat,either Pb or Li and those dc/dc up converters from ebay. Some op at 1..1.5mhz, could they be sufficiently shielded/filtered ?

[@MIKROWAVE1]

The B+ current drain is very low. Below 25 mA, so theoretically a couple of days constant on. Just playing off and on about a year.

[@DAVIDGREGORYKERR]

Using Philips/Raytheon vacuum tubes you could make the radio a lot smaller.

[@MIKROWAVE1]

OOOOOOH yes - Yes we could.

[@tomstrum6259]

Success !!! ......Finally Identified the source of my Many strong mystery"Squeel" AM signals using a Frame loop antenna.....Using my "tinySA" spectrum Analyzer, I located the Source of the Spurious signals.... My little "ROM" AG-03M guitar Amplifier is emitting 3 Strong In-band AM off frequency Carriers probably Causing a multitude of strong interfering Heterodyne carrier Tones.....Replaced with LM386 amplifier & All 90% squeals Eliminated !! ......May help others having similar problems.....

[@MIKROWAVE1]

That Dirty Little Practice Amplifier! Hee. Maybe strap a complementary pair of transistors off the end of that LM386 and get the monkey to swing! www.bristolwatch.com/radio/lm386_power_amp.htm

[@SanderOlbermann]

great receivers series.

[@MIKROWAVE1]

Thanks for watching! Sometimes I like to pop back over to tube stuff. Without getting anyone too SHOCKED.

[@Mold0vanin]

Хорошо. Познавательно.

[@ultrasoundguy1]

I noticed your reception is completely free of switcher hash. The only time that's true in my location is when the power goes down. Are you in a rural area? If so, I need to move. :)

[@johnwest7993]

Me too.I live in a city and my living-room window looks out over an alley. When I look out my window I'm staring from 10 feet away at power lines for 3 different apartment complexes. The only type of antennas I use are very high Q antennas. I see the noobs with ham KZbin channels think high Q antennas are a bad thing. They will learn.

[@JCWise-sf9ww]

Power companies are using those smart meters so they don't need to send a meter reader person out to read the KWH. Their meter communicates over the power line back to the substation the KWH you use, at lease they do were I live. The smart meters, cellphone chargers and switching power supplies in your electrical appliances/electronics cause a lot of the buzzes and hash noise on AM radio receivers. They don't put in enough filters to keep from interfering with AM, do they really care?

[@ultrasoundguy1]

@@JCWise-sf9ww On the one hand I understand the extreme cost constraints when designing a CFL or LED light bulb that sells for less than a buck, but allowing the airwaves to become so polluted is just unacceptable. Tesla for example solved their AM interference problem by not having an AM radio in the car, and now there's even discussion of doing away with broadcast AM entirely. Rather than that, what needs to happen is regulatory enforcement that in turn stimulates a technical advancement to create a class of RF-quiet switchers or a switcher alternative. Right now there's no need for that since they're allowed to radiate in an unregulated manner below 30 MHz. So I guess we all need to move to a rural area to avoid the S9 hash.

[@JCWise-sf9ww]

@@ultrasoundguy1 I Totally Agree 1000%. The China made cheap electronics are notorious for not using line filters in their power supplies. I actually took the line filter out of a computer supply and put in a TV converter box and had to change out the 12 volt power for a stereo amp my son is using. other wise AM radio reception suffered.

[@MIKROWAVE1]

I have hash at times and in some bands. Noise cancellation techniques do help in my situation. But in general in my city edge cul-de-sac of houses, I call this a suburban neighborhood. I have close neighbors but a nice woods out back. So not "remote pristine", but not bad for noise.

[@gretalaube91]

Doesn't all that grounded test equipment next to your loop do something bad to the big loop? Works better outside!

[@MIKROWAVE1]

Yes and Noise...But they also represent a place that conducts signals to the basement so there are benefits too.

[@tomstrum6259]

Very Enjoyable & Informative video on AM broadcast Frame loop Antenna performance using Vac tube Regen radio....Why is it Only about 50% of your Moderate to strong signal Strength stations are Detectable with Clear audio & the other Moderate strength Stations just squeel Regardless of Regen pot adjustment almost like your Detector is going into Uncontrollable oscillation or Feedback ??....My Similar loop Frame antenna + similar Pentode Regen receiver does Exactly same thing with Strong to Moderate strength signals that Can't be Demodulated to clear Audio regardless of Regen potentiometer setting....

[@hobbyrob313]

Hello sir, it's all very nice but here around the Netherlands medium wave is unfortunately out of fashion! I don't want to say it ugly but it is becoming more and more extinct. rather let your receiver work on SW Short Wave please? (could this also do FM???) ;-) Healthy and Kind Regards! Rob

[@MIKROWAVE1]

Well yes, Shortwave as well with smaller coils, but I highly suggest a metal chassis and a Vernier Reduction Dial. It is even getting hard to tune accurately on the BCB with the kind of selectivity we are achieving with these High Q inductors.

[@AdamosDad]

✋73's🎙KD9OAM🎧📻📡