Double Regen Receiver

[pwdrive]

Quite a nice interesting circuit:

Scroll down to page 127 when the PDF reader opens up.

http://www.rsp-italy.it/Electronics/Maga...938_03.pdf

Lawrence.

[AlanBeckett]

Lawrence,

Page 127 is 'The 510X Frequency Expander'.
Is that it?

Alan

[Mark R]

Big Al
page 15 has a double regen superhet on it.

cheers Mark

[AlanBeckett]

Ah, so

Alan

[Radio Fixer]

It took me a while to find that its for the 14 -28 m c/s band. So does it work like this:

Mixer 6L7G and Osc 6J5G produce a 1600 k c/s IF and no amplification is used. The 6K7G is the detector and the 6K7 its BFO and are only coupled by physical proximity. The BFO 'beats' the IF to audio that is heard in the phones.

All this Ham stuff is an area I have never ventured into. Is there anything on the 14 -28 m c/s band these days? Wouldnt be too happy with HT + directly on the phones!

Looked through the rest of the Mag... Luv all the old ads

Interesting, thanks Gary

[Radio Fixer]

That would be over 10 - 21 metres and according to this chart http://en.wikipedia.org/wiki/Shortwave_bands not very exciting.

I did have a tune over it and found 1/2 dozen stations (spanish speaking, arab etc) all with lots of noise.

G

[pwdrive]

It took me a while to find that its for the 14 -28 m c/s band. So does it work like this:

Mixer 6L7G and Osc 6J5G produce a 1600 k c/s IF and no amplification is used. The 6K7G is the detector and the 6K7 its BFO and are only coupled by physical proximity. The BFO 'beats' the IF to audio that is heard in the phones.

All this Ham stuff is an area I have never ventured into. Is there anything on the 14 -28 m c/s band these days? Wouldnt be too happy with HT + directly on the phones!

Looked through the rest of the Mag... Luv all the old ads

Interesting, thanks Gary

Hi Gary, yes, no IF amplifier as such, the mixer regen is a standard Hartley affair, the detector regen is electrically the same but they use a seperate cathode coil as opposed to a cathode tap as is the case with the mixer, screen grid control for regen is the norm for pentode regens.
The receiver covers all the main Amature bands from 3.5 to 28 Mhz.
Tuning through the shortwave spectrum with a non BFO domestic radio won't reveal to much other than standard AM broadcasts, even so DXing some of these stations can be quite a challenge and a skill.
The Amature bands will either bore you stiff or fascinate you, I have always been interested in those bands, I still find that getting across the world with just a few watts amazing, still plenty of CW working even today.
My Regenerodyne project does not have an IF amp either, the IF is centered around 2.5 Mhz and is tunable, it being fed direct to a regen. detector, for what it is the performance is top notch. Yes the 250v on the headphones isn't to cool by todays standards.

Lawrence.