slow AC-30 clone build.
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Re: slow AC-30 clone build.
You could also just wrap the wires around the terminal and solder in place after a tight crimp with pliers to ensure solid physical contact.
~Phil
~Phil
tUber Nerd!
Re: slow AC-30 clone build.
Thanks Martin, I've decided I will go that path with the amp. Looking at the tag strip I used, it's only suitable for components and one or two wires. The Keystone tag strip has more real estate.
I had thought of adding fly leads to the ends of the wire, but rightly or wrongly, why add another solder joint if you don't have to. There is the potential there for another dry joint, and I'd probably be wise to use high temp solder as it is harder. The stuff we used at work was Alpha 38, I think it resisted vibration which is the reason we used it.
I had thought of adding fly leads to the ends of the wire, but rightly or wrongly, why add another solder joint if you don't have to. There is the potential there for another dry joint, and I'd probably be wise to use high temp solder as it is harder. The stuff we used at work was Alpha 38, I think it resisted vibration which is the reason we used it.
Yours Sincerely
Mark Abbott
Mark Abbott
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Re: slow AC-30 clone build.
Hello Mark,
Any updates on your AC30 build? I received my transformers a little while ago.
Cheers,
Dave
Any updates on your AC30 build? I received my transformers a little while ago.
Cheers,
Dave
Re: slow AC-30 clone build.
I’m interested in finding out the rail voltage and what I’ll deem acceptable.
I should have bought the low voltage Haddon transformer.
I should have bought the low voltage Haddon transformer.
Yours Sincerely
Mark Abbott
Mark Abbott
Re: slow AC-30 clone build.
Well, I did say it would be a slow build. Here is a bit of progress. I have had issues with the Mercury Magnetics power transformer putting out 303-0-303vac.
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Yours Sincerely
Mark Abbott
Mark Abbott
Re: slow AC-30 clone build.
Is that its unloaded voltage, or with a full compliment of valves drawing current?
My band:- http://www.youtube.com/user/RedwingBand
Re: slow AC-30 clone build.
I should have power on the output stage soon, but I think it is loaded with power on it. I will report back.
Yours Sincerely
Mark Abbott
Mark Abbott
Re: slow AC-30 clone build.
Hi Mark,
Mercury specifies all of their voltages as unloaded. I believe you have the Woden AC30 clone PT, MMP-V30W. I have the Haddon, MMP-V30H-M for my AC30/4 build.
See here:
Woden PT Haddon PT
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Re: slow AC-30 clone build.
I have the output stage wired up with an 82 ohm cathode resistor. The secondary measured 305-0-305vac unloaded and 297-0-297vac with the load of the four EL84’s. The preamp and P.I. stages haven’t been built yet.
The B+ going to centre tap of the output transformer measures 360VDC. The screen grid node measures 352VDC. The voltage on the 82 ohm cathode resistor is 12.8VDC. The cathode resistor get quite warm even though it is rated at 25 watts. The total current is 156.8mA and the voltage is 12.8VDC, that equates to 2 watts there about.
The output valves are running between 109% and 114% of their total plate dissipation. Though I am measuring screen current too through the 1 ohm resistor on each valves cathode.
I think it is safe to say something has to change with regard to the power transformer's output voltage.
The B+ going to centre tap of the output transformer measures 360VDC. The screen grid node measures 352VDC. The voltage on the 82 ohm cathode resistor is 12.8VDC. The cathode resistor get quite warm even though it is rated at 25 watts. The total current is 156.8mA and the voltage is 12.8VDC, that equates to 2 watts there about.
The output valves are running between 109% and 114% of their total plate dissipation. Though I am measuring screen current too through the 1 ohm resistor on each valves cathode.
I think it is safe to say something has to change with regard to the power transformer's output voltage.
You do not have the required permissions to view the files attached to this post.
Yours Sincerely
Mark Abbott
Mark Abbott