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Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
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15th Oct 2006, 4:26 pm | #1 |
Nonode
Join Date: Jun 2004
Location: Norwich, Norfolk, UK.
Posts: 2,543
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OA70 diode equivalents ?
The OA70 inside one of the IFT's of my Bush TR82 is open circuit. Are there any other diodes that I could sub it for?
Thanks David |
15th Oct 2006, 4:51 pm | #2 |
Rest in Peace
Join Date: May 2003
Location: Harlaxton, Lincolnshire, UK.
Posts: 3,944
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Re: OA70 diode equivalents ?
Hi David
An OA91 would do fine if you have one, the important thing is it must be a germanium type, silicon won't do due to the relatively high forward voltage drop. You could try using the emitter-base junction of an old small-signal germanium transistor. |
15th Oct 2006, 4:57 pm | #3 |
Rest in Peace
Join Date: Jul 2004
Location: Dartford, Kent, UK.
Posts: 1,661
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Re: OA70 diode equivalents ?
Hi Dave, The OA70 is listed as a video detector diode, Perhaps Bush had large stocks of them. I think almost any germanium diode would be fine as an AM detector, Try OA79, OA81, OA90, or OA91.
Regards, Mick. Last edited by Darren-UK; 28th Dec 2007 at 2:13 am. Reason: Excessive use of emoticons. |
15th Oct 2006, 6:50 pm | #4 |
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,943
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Re: OA70 diode equivalents ?
You will find at least one suitable detector diode in any scrap trannie. As Colin says, most base-emitter junctions of germanium transistors should work too.
A silicon Schottky diode should also work, though I've never actually tried one. Paul |
15th Oct 2006, 7:08 pm | #5 | |
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,571
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Re: OA70 diode equivalents ?
Quote:
Rich.
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