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Old 28-11-2005, 10:54   #31
dk8cb
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@ mitajohn

I doubt a little that increasing the voltage to 15 V will still decrease the capacitance much further or at least sufficiently to reach 22 MHz.

Roland
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Old 28-11-2005, 16:15   #32
mitajohn
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Hi Roland,

The DC/DC converter circuit does not work with any other 12, 13 or 15V Z-diode (if it is a zener) except the one installed. If we had a schematic would be helpful, but it's not worth trying. Any way the loop amplifier works up to 27 MHz and I checked it that it works very good up to 21475 kHz with some directivity and a lot of noise.

John.

Last edited by mitajohn : 28-11-2005 at 16:33.
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Old 29-11-2005, 19:58   #33
Rene Schmitz
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Hi Mitajohn, Bernd and all,

Thanks for the notes.

It would seem that a deep null is better with a balanced loop. Could be interesting to duplicate the FET amplifier, and use a transformer for matching them to coax. Obviously the varicap would need to be made "floating" between the ends of the loop then.

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René
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Old 30-11-2005, 09:36   #34
dk8cb
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Quote:
Originally posted by Rene Schmitz
... Could be interesting to duplicate the FET amplifier, and use a transformer for matching them to coax. Obviously the varicap would need to be made "floating" between the ends of the loop then.


...and the FETs would have to be matched as well, preferably as two on the same substrate.

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Old 22-12-2005, 17:37   #35
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Hello,

during my last business trip to Japan I could receive the label of DW from Sines on 15440 with the Degen. With 3 m wire no reception was possible. Listening in AM the signal from the Degen was much less noisy than the 3 m wire, both mounted in the hotels window there in the center of Tokyo.
The potentiometer of my 1st Degen has been broken before the trip. I replaced the broken potentiometer and contacted the seller in China for a fitting potentiometer. He offered me to send a new antenna without returning the defective one if I pay the postage. Now I have 2 Degen antennas and I would sell the repaired one (see attachment) only for the additional postage I payed. Since having repaired the DC-Box I miss a clamp to contact the batteries. Therfore replacing the batteries means to solder a little!

Bernd, DF9RB
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Old 23-01-2012, 08:27   #36
jabi
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Any have the following pictures:
http://home.arcor.de/carsten.knuetter/DE31_inside.JPG
http://home.arcor.de/carsten.knuetter/DE31_inside1.JPG
http://home.arcor.de/carsten.knuetter/DE31_inside2.JPG
Is impossible download for this page.
73,s de Jabi, EA2ARU.
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Old 23-01-2012, 16:03   #37
simone
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Hi jabi,

I am not sure if Carsten still reads on the forum regularly, better send him a PM (username: carknue), maybe he still has the photos you are looking for.

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Old 24-01-2012, 19:13   #38
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Quote:
Originally Posted by jabi

The links are working again.
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AOR 7030 + Wellbrook ALA 1530P & DWT + Degen DE31 + TG33

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Old 25-01-2012, 10:15   #39
mvs sarma
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Many thanks , carsten !! it is much useful for hobbyists. we get the concept. but the intervening telescopic which helps to make proper shape of the antenna, i doubt whether is is connected on any side to the antenna?
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Old 27-01-2012, 18:03   #40
jabi
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Pictures ok !

Pictures all ok. But, is possible, please, upload the circuit squeme for work (and play) with it?
Regards de from Bilbao, Spain, de Jabi, EA2ARU.

P.D.: I am looking the more little antenna for RX in the ham 40 mtrs. in my SOTA RX informations. Have aucun experience with the BAZ ferrite antennas for RX on 40 mtrs.?
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Old 31-05-2012, 05:26   #41
ianf
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I use the Degen all the time with my Newstar, top tip, make sure Degen has really fresh batteries, it makes a big difference
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Old 12-02-2013, 21:20   #42
Linux-DRM
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31MS

Although not normally a fan of active loops the Degen 31MS performs very well on shortwave and medium wave. I picked up VOCM on 590kHz, Sunday morning, not booming but good copy (using the antenna direct, not via the coupler). OK, VOCM is not that hard to pick up in the UK in the grand scheme of MW DX but still not bad for such a simple setup. I was using my trusty Ten-Tec RX320D at the time using an unattended recording setup to my ultra low powered UG802 mini PC running Ubuntu.

Cap
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Old 28-11-2016, 10:23   #43
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Uniwave Diwave 100 + Sony Active Antenna ANLP 1

Excellent combination! Strong signal from All India Radio, Voice of Nigeria, listening in Brazil. It's amazing!
I listened too:
BBC WS to Cuba;
Vatican Radio to USA;
Radio Romania International to France;
Radio New Zealand International to Pacific.
Clint 73!
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