Transformer Questions

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Kcz5o
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Transformer Questions

Post by Kcz5o »

I recently put together an 18 watt kit and was happy with the results. I decided that I would be adventurous and try to Put together a JTM45 but source the parts myself. I think I may have bought the wrong transformers. I think the PT will work but would like some feedback about it. I don't think the OT will work because the impedance is different. I am hoping someone that knows more about it than I do could help.

I used the Tube Depot JTM45+ as a guide. The the transformers that it calls for are labeled TD. The ones I bought are labeled other. I have not started to assemble anything yet so maybe I just need to order a different OT.
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crgfrench
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Re: Transformer Questions

Post by crgfrench »

3.6k is the wrong impedance . You want 8k.
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Kcz5o
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Re: Transformer Questions

Post by Kcz5o »

Thats where I confused myself. I purchased the hammond transformer that has the 8k for a JTM45 but the tube depot parts list is calling for the 3.6 for a 50 watt amp. I've attached the TD instructions. Can the hammond transformer be split in half and make it 3.6k. I hope I'm making sense.
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crgfrench
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Re: Transformer Questions

Post by crgfrench »

What output tubes do you plan to use in this?
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Kcz5o
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Re: Transformer Questions

Post by Kcz5o »

EL34. I've attached schematic.
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crgfrench
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Re: Transformer Questions

Post by crgfrench »

Oh. 3.6k is correct if you're using a pair of EL34s in push-pull.
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Kcz5o
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Re: Transformer Questions

Post by Kcz5o »

Can anyone tell me if the 700cvt@200mA power transformer can be substituted for 690cvt@150mA power transformer? Thanks for all the help so far.
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geoff 1965
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Re: Transformer Questions

Post by geoff 1965 »

i think the one you bought is more suitable! are'nt tube depot pushing it with 150mA HT for a GZ34 & 2 EL34's?
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Kcz5o
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Re: Transformer Questions

Post by Kcz5o »

Yes that is what they are calling for. My head is starting to spin looking at transformer specifications :-)
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