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June 09, 2026, 11:03:56 am
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1
Tube Amp Building - Tweaks - Repairs / Re: Tube Preamp SMPS
« Last post by Jonas on June 09, 2026, 08:51:17 am »
thanks Pete and nice job! - I will give that a try

Are you getting any noise form the 6.3v heaters?

I an not using the on-board dc jack, wiring direct (tried to upload a pic no success - attachment options is not working for me???)
2
Tube Amp Building - Tweaks - Repairs / Re: Tube Preamp SMPS
« Last post by Jonas on June 09, 2026, 08:47:46 am »
test
3
Tube Amp Building - Tweaks - Repairs / Re: Any tips for taming a wild 5E3?
« Last post by pdf64 on June 09, 2026, 08:19:08 am »
Voltage survey?
Volume pot taper?
4
Video Clips / Rush "Fifty Something" Tour at Kia Forum Inglewood LA 7th June 2026
« Last post by Rontone on June 09, 2026, 08:00:23 am »
Decent audio, their new drummers awesome

5
Tube Amp Building - Tweaks - Repairs / Re: silvertone 1484
« Last post by passaloutre on June 09, 2026, 07:59:06 am »
Mojotone used the 6CG7, and EHX still make one.
6
Just trying to be lazy and get away with it  :icon_biggrin:

But does seem its best for tape motor devices, I have a lot with short legs intended for PCB so they won't quite squeeze on there,

I've ordered some Class X2 68nF with long leads to replace this old 50nF which is an early 70s Erie Duolectric which probably could fail short

7
Tube Amp Building - Tweaks - Repairs / Re: Any tips for taming a wild 5E3?
« Last post by isaac_teller on June 09, 2026, 06:16:54 am »
If you have a 12AX7 in V1 try a 12AY7 instead. If still too much' try a 12AU7.
8
Tube Amp Building - Tweaks - Repairs / Re: First amp build
« Last post by Mongrel714 on June 09, 2026, 04:39:35 am »
I'm not crazy about the bias power supply switching off with the Standby switch.

Yeah, and the fusing on the Secondary HT can be better, have a look at some standby and fusing ideas here:-

https://www.valvewizard.co.uk/standby.html

https://www.valvewizard.co.uk/fuses.html



Will this work? if not which way should I go??

9
Tube Amp Building - Tweaks - Repairs / Re: First amp build
« Last post by Mongrel714 on June 09, 2026, 04:36:23 am »
Neither layout in this thread gets the standby switch correct to the schematic they're noted to be based on.
Both disable the bias supply whilst in standby mode, thereby causing an enormous cathode current surge when standby is flipped.
Because the bias supply takes much longer to charge up than the anode and screen grid HT supply nodes.
Ok, got it!
10
Tube Amp Building - Tweaks - Repairs / Re: silvertone 1484
« Last post by johnfromcyrene on June 09, 2026, 02:14:54 am »
I posted the mojotone schematic and layout at the top.
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