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I am looking for the specifications for a Zenith power Xformer. The Zenith part number is 95-705. It is used in a Zenith 6-S-597. Here is a link to the xchematic:
http://www.nostalgiaair.org/Resources/204/M0025204.htm
I am thinking it might be a 275-0-275 volt @ 125 ma. secondary with a 6.3 volt 3 amp filament winding.
Am I close?
Is there any web site that has Zenith part specification, especially for their power Xformers?
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HV current is too high. Only need 50ma or so.
Terry
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Try Edcore,, if you need a close electrical replacement, or see if you can find a used one that close, or find a NOS generic replacement like a Stancor, a Thordarson, etc. Brand Z transformers were notorious for being marginal at best so just about anything would be an improvement. Oh look, the dummies used a 6X5 to power a 6F6 output tube, and they are running it with 368 VAC on the plates and an output voltage of 325 VDC, not smart. The 6X5 has a max voltage rating of 325 VAC on the plates and current output 70 ma, did these geniuses leave their tube manual in the drawer when they designed this thing? The Philco sets that use 6X5s run them at much lower plate voltages, they used 41s or 6K6s, not 6F6s, and they used bigger power transformers. But the order of the big black dial will just keep repeating to themselves that the evil 6X5s are to blame, not idiots at brand Z ignoring tube specs.
I'm not big on altering a radio but the power supply in this set is so badly designed that you should do one of two things: Use a power transformer that has a lower voltage high voltage winding, and keep the 6X5, maybe keep the 6F6, but consider using a 6V6 in it's place, or a 6K6 but that involves using a new output transformer due to the plate impedance. Get a larger power transformer, with a 5 volt filament winding, with the same 350/368-0-350/368 volts on the high voltage side, dump the 6X5 replacing it with a 5Y4/5Y3, and keep the 6F6. Make sure that the speaker filed coil is alright, that may be toast too.
Regards
Arran
(This post was last modified: 08-06-2014, 03:45 AM by
Arran.)
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Agree, these sets are not too critical about specs; anything with at least 400 VCT winding at 50 or more ma rating should be fine. It's always OK to use a replacement with a higher current rating, if it physically fits on the chassis. If you are going to use a 5Y3, your replacement transformer must have a 5 volt 2 amp winding. You could also use a pair of 10 cent diodes instead of rectifier tube.
Assume you are going to or already have replaced the electrolytics and paper capacitors. Add a fuse (1 amp should work,) on the AC line for safety. Yeah, check the wiring and field winding too.