Ceriatone JTM45 clone build issue - low buzzy output

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supertgtr
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Ceriatone JTM45 clone build issue - low buzzy output

Post by supertgtr »

I had this amp kit built for me by an amp builder friend of mine, and we're getting low buzzy output. He had a bit of trouble with installing the output transformer. I'm wondering if it's an impedance mismatch? It should be wired for 8ohm, but if he accidentally wired it for 16ohm, would that cause the problem? The output transformer is a Mercury Magnetics 045RS-L
I attached a gut shot of the build. Please take a look, and see if there's anything that would cause a red flag. Thanks!
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billyz
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by billyz »

Check youR OT wiring. The colors look wrong to me. It almost
Looks like
It is wired backwards. Like secondaries and primaries are on the wrong side of the tube. Whats the green w white strip wire ? Never seen that on the primary side. And the red/blue/brown on the output?
supertgtr
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by supertgtr »

Thanks for the tip!
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billyz
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by billyz »

Not sure what the switch is ? Triode/ pentode ? I always found
I needed a small value resistor between the screen and plate. I never found it very useful anyway and always preferred Pentode.

I would disconnect the triode pentode circuit until you sort things out.
Jana
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by Jana »

Could catch Billy. I would have thought the same thing but they have some strange wire colors on that transformer.

http://mercurymagnetics.com/images/tran ... 45RS-L.pdf
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CHIP
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by CHIP »

I don't see the black wire from the OT tied with the brown and white wire. According to the Merc. Mag. diagram that Jana linked , for an 8 ohm load those 3 wires should be tied together.
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billyz
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by billyz »

Well I'll be. Guess they are correct on the primary side. Lots of options on that one. Just delete everything I thought.
thejaf
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by thejaf »

Might be irrelevant to the problem discussed, but I don't see much if any solder for the ground buss connection (green wire) at the input jack.
supertgtr
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Re: Ceriatone JTM45 clone build issue - low buzzy output

Post by supertgtr »

It turned out to be an incorrect bleed cap that was in the kit.
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