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37-84
#1

Problem: Open Primary on the OSC coil.

I've searched through the information here and on ARF regarding this common problem, but have a couple of questions for someone who has perhaps rewound one of these recently.

I measure 3.1 ohms on the secondary. What should the primary measure?

I've read anything from 14 turns and 25 turns of 36 to 40 ga wire. Before I start unwinding...and lose count...does anyone know which it should be?

I had an extra OSC coil from a model 89 that I rewound years ago and I tried it on this model 84. I was able to get the local (strong) station in at full volume faintly. It does get a bit louder when I touch the antenna wire I have connected (but not as loud as it should). That coil measures 6 ohms on the primary and 5 ohms on the secondary.

I then tried one of those AES replacement OSC coils and couldn't get a single station to come through with it. The model 89 coil worked better.

Could the low volume be caused by too much resistance on the model 89 coil? The secondary on the model 89 coil has a lot more windings than on the model 84 coil.

I measure 180 ohms from the antenna clip to GND with the volume control all the way open (and the set off). I *think* the ANT coil primary is good based on that?

Here's the schematic:

   

Greg V.
West Bend, WI
Member WARCI.org


Messages In This Thread
37-84 - by NostalgiaRadioTime - 03-18-2018, 10:36 PM
RE: 37-84 - by Radioroslyn - 03-19-2018, 12:41 PM
RE: 37-84 - by NostalgiaRadioTime - 03-19-2018, 10:28 PM
RE: 37-84 - by Radioroslyn - 03-19-2018, 11:20 PM
RE: 37-84 - by NostalgiaRadioTime - 03-20-2018, 10:29 PM
RE: 37-84 - by 462ron - 03-21-2018, 03:55 PM
RE: 37-84 - by Radioroslyn - 03-21-2018, 08:55 PM
RE: 37-84 - by 462ron - 03-22-2018, 09:39 AM
RE: 37-84 - by NostalgiaRadioTime - 03-23-2018, 10:49 PM



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