Single signal reception on a regenerative receiver. Is it possible?
Vložit
- čas přidán 5. 09. 2024
- Regenerative receivers, like simple direct conversion sets, are not known for their single signal reception. But is is possible?
Watch this video and find out. I'll describe an unusual regenerative receiver which contains no LC tuned circuits yet offers high stability, easy tuning and a degree of single signal reception on the upper sideband (ie your local oscillator is set below the CW signal that you're receiving).
To build this unit visit F5LVG's website at oernst.f5lvg.fr... and check his high performance regenerative receiver. Build it using normal inductors and capacitors. When happy substitute ceramic resonators and check its performance.
I use 7.160 MHz ceramic resonators to give 7.000 - 7.120 MHz coverage - ideal for CW and some SSB signals. They are available at: www.minikits.co...
PS: If you liked this video please consider supporting Amateur Radio VK3YE by:
* Subscribing on CZcams,
* Checking my books page at books.vk3ye.com
* Shopping on Amazon via: amzn.to/3iiDQXv, or
* Shopping on eBay via: ebay.us/i9DuWP
(then if you buy something I'll get a small commission at no cost to you)
because of how narrow the bandwidth can be with a well designed and built regen with good components you can easily get slope each side of the signal changing the pitch while tuning in .
I have just started to gather the bits to have a go at this. That regen control looks perfect I have never managed to build a regen with a smooth control like that.
Excellent circuit and presentation VK3YE. Nice sharp, clean sounding CW every bit as good as any DC receiver I have heard or used. I built a single tube (double triode) regenerative receiver with plug in coils but it does require more adjustments than yours. I also use a vintage National SW-3 R-Rx. The quality, heavy duty components and well laid out construction built by a generation of real craftsman certainly shows when using this fine receiver. 73!
I would have thought a regenerative receiver would be essential for receiving SSB and CW signals so as to push past the normal oscillation.
Hi Peter, the single signal reception part is interesting but I think that it's not really the same thing in this case. If the circuit is oscillating while tuned into the top half of the signal it's still going to respond to the lower half should someone key up. It seems quite a bit different than the action of a crystal filter in this regard. It's not high Q chopping the signal, it's just losing puff :)
Thanks to the great initial idea by vk3ye, sv3ora has extended it to a far better level, but without making it much more complex. See his page qrp.gr/regenrxcer/ for the two improved versions of the receiver. The one at the beginning of the page is the bare bones version, and the one at the bottom, is the special one.
Both versions, include a much better and quieter headphone preamplifier. The special version includes a simple but good performance SSB and narrowband CW filter. There is also no audio oscillation at extreme regeneration values in his version, compared to the vk3ye one.
His receiver uses a varicap, which eliminate hand effects, it is cheaper and it can be controlled with precision without special verniers. This is indeed a USB RX without any coils or variable capacitors, and it is a great performer!
I have built it and with just 3 resonators, I could cover the hole 40m region 1 band without gaps.
Believe it or not, the performance is so good, that I have abandoned listenning to the 40m band using my IC-728. This ultra simple homemade RX is just so much quieter, like the modern $$$$ rigs.
I need to join SPRAT....Great video ...Thanks Peter!
I have a big problem... you say we should first make the original design and then replace the tuned circuit to a ceramic resonator. My problem is that I really don't know how to do that, that's why I searched for an already-made receiver that uses a ceramic resonator. Please help :)
I don't think there are ready-made receivers that use a ceramic resonator. I suggest building several regen receivers that use the conventional inductor and variable capacitor. Learning electronics and radio practically takes time - and not everything will work first go. So keep persisting and eventually you'll have more and more successes.
Why not use a audio frequency multiplier so that you tune to NEARLY zero beat for cw, lets say 50hz high, Then frequency multiply the resultant audio to 600 hz. With a 70 hz low pass filter on the audio input to the frequency multiplier, the bandpass width would be 140 hz. Therefore the radio would be essentially single signal reception.
8:10 "...I HATE cw..!" :P Thanks for share it..! Amazing project..!
Very nice
Very nice receiver
Im wondering could this be used as a IF amplifier\Det?
If I used a 3 pin xtal filter @ 10.7/10.695mhz.@7.5khz B\W
Would I need to pull freq for USB and LSB modes but not Am mode?
Could I add 3 regen trim pots for each mode i select optimised for each mode?
Rob 73's
Gw1CSU
Good stuff Peter thanks for sharing
It's not single-signal reception if the only way to reject "the other side of zero beat" is to turn off your BFO as you tune across zero beat -- what is what's happening when the receiver "runs out of puff" during the demonstration. Single-signal reception is about rejecting the other side of zero beat while you're receiving the _desired_ side of zero beat _with your BFO turned on_. Amateur radio W9BRD.
I really liked the content of your channel, congratulations! I also really like Regenerative Receptors, including some on my Channel, where I share the PCB's layout and layout. Success friend!
HI Peter
I see you use the vernier dials on a few of your rigs.
I cant find them any were, are they still available?
Joe g4vdx
Can it work with a varicap in series with a fixed capacitor?
Amazing