Real radio :-)

[Andre Kesteloot]

Gerald,
Thanks for your input.
Incidentally, for the benefit of AMRAD readers, here is a picture of the 
beast.

http://www.desyatnik.com/restoration/torn_eb_45_restoration.php

The US Navy, as you probably know, had also developed a 
supper-regenerative receiver but fearing leakage from the RF stage, 
decided to go for a totally RF tuned, multistage receive.
For a while, I owned the next iteration of that US Navy receiver.
It weighed about a ton, and one day, moving it from one room to another, 
i almost dropped it on my dog !
The picture above certainly shows German technology at its best
73
André  N4ICK

On 12/5/2010 8:33 PM, Gerald Wolczanski wrote:
> I don't know about "real radio" but a few months ago, I cobbled together
> some power supplies and put my "Torn.E.b." TRF regenerative receiver on
> the air.  The nameplate on my says 1943.  I've been chasing beacons on
> the longwave band.
>
> See:
> http://www.noding.com/la8ak/22a.htm
>
> I have a 22kW AM station 3km from my QTH and the little Torn doesn't
> know it exists.  My new Palstar R30A, with a "modern" design (and
> reasonable dynamic range) is brought to its knees by that AM station.  A
> wavetrap is the only fix.  Without it the band is a buzz with IMD
> products and de-sensing.
>
> Aside from the lack of single signal reception on CW, the little Torn
> holds its own.  I often toggle back and forth between the two (the R30A
> also has a very steep skirted Collins filter and a W3NQN audio filter)
> and I can almost always hear signals just as well on the regenerative
> receiver.
>
> The Torn's lack of AGC, and good fidelity and dynamic range in the audio
> stages, also makes for a nice listening experience...up to a point when
> the high fidelity lightning crashes begin to hurt the ears!  Many modern
> radios (my R30A included) have too much AGC.  The result is a muffled
> output and weak signals alongside strong signals are lost in the gain
> turn-down.  That may be the best part about good direct conversion
> receivers - the ability to listen to a weak signal in the presence of a
> strong signal.
>
> I got my Torn.E.b. at a hamfest for $5 - the guy did not know what it
> was.  I surely did, having read an old article, years before, in CQ
> magazine about this old receiver that was so good (and spurious free)
> that it was used as a lab instrument.  Now it's my Beacon instrument.
> har!
> Jerry W
> KI4IO
>