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Old 25th March 2012, 06:28 PM   #1
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Default Any use for these PAECO transformer?

I found two of these transformers at my local surplus and got them for almost nothing. These were used on a HP 200CD oscillator isolating the cathode follower output into a 600ohm spec'd load. It is T2 on the schematic and was used only from 1 to 6000 hz. I has close to a 2:1 ratio. All three windings have 10mH and around 130ohms. They are decent in size and heavy. According to my calculations the FR is .3db up at 10K and 1.5db up at 20K.

Could these be used for something or are they just trash?

Attached Images
File Type: jpg paeco transformer 1.JPG (45.3 KB, 229 views)
File Type: jpg paeco transformer 2.JPG (62.1 KB, 219 views)
File Type: jpg hp200cd.jpg (183.8 KB, 221 views)
File Type: jpg paeco tr1.jpg (37.5 KB, 214 views)
File Type: jpg paeco tr2.jpg (37.6 KB, 206 views)
File Type: jpg paeco tr3.jpg (37.8 KB, 20 views)
File Type: jpg paeco tr4.jpg (37.8 KB, 25 views)
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Old 25th March 2012, 06:54 PM   #2
kevinkr is offline kevinkr  United States
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I just realized that there are actually two transformers in the oscillator, and the ones you have were used to 6kHz, it is possible that they have more extended frequency response than stated assuming that the switch over to the other transformer at 6kHz was to maintain distortion performance. You'll have to measure them to see for sure.
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Old 25th March 2012, 07:12 PM   #3
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I have run some frequencies through it. See pictures in post, frequencies at 10hz,1K,10K and 20K. But the 2:1 ratio may not be very useful.
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Old 25th March 2012, 10:08 PM   #4
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I saved about 20 of these oscilators from the crusher about 10 years ago. Mine were a later version using a solid state rectifier and 6CW5 output tubes. The low frequency transformer is exactly the same though. I haven't found much to do with these things yet. I gave most of them to the metal scrap guy, but still have a few around. If I remember right the high frequency transformer is an air core deal. I didn't save any. The power transformer is just right for a 20 - 30 watt guitar amp and thats where most went.
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Old 25th March 2012, 11:04 PM   #5
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Maybe I can remove a portion of the last winding and get to something useful for a cheapo project. Worse case i can save the core a some day try winding a PP transformer.

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Old 26th March 2012, 01:44 PM   #6
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2400 Ohms center-tapped to 600 Ohms - not that useful, as you need push-pull or parafeed. With parafeed, you could wire it as an autotransformer for 5.4K to 600 or other 9:1 ratio.

I have a few of these - anybody want 'em for the postage?
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Old 26th March 2012, 08:56 PM   #7
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could be usefull if you had some philips 800 ohm stuff lying around . would put you in the 3K primairy region .

v4lve .
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Old 29th December 2012, 07:54 PM   #8
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Default May be good for Pass F6

I may have finally found use for these. I have been following the Pass F6 thread that uses a 1:1 dual secondary input transformer for phase splitting duties on a power jfet class a amp. I have ordered some of the semisouth devices and will soon give them a try.
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