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I think it was as follows: Little Dot MK2 Mkii 6J1 X 2, and 6N6 X 2 Tubes, with the 6J1's each powered by a set of yellow/7.5Vac (no rectifiers) secondaries and 6N6'S powered by 9.5Vac (blue and white) secondaries that was then rectified? So I'm thinking blue and white secondaries paralleled...

Morning, question re secondaries in parallel  :thinking: Thinking of rather using 9.5V secondaries for the heaters as I want to use a LM317 circuit and voltage drop will be to much for 7.5V secondary. 1.  As both blue and white secondaries are 9.5V, can I connect them in parallel/both to...

:rubhands:

Yes, will measure tomorrow, thx

Agree.  But there's no logic in those taps, thought the brown ones was for 110V input, will check then again.  Surely with only one transformator and 4 valves there must be secondaries for HT? But Handsome's post might just clear up some questions etc.  Will get more 5W resistors and caps...

Thx Handsome, that actually makes a lot more sense now.  So we learn

MusicMan_ZA , think it will work, just add connection between C2/C3 and R2/R3.  Not sure why, but it's connected on the suggested schematic.  Don't know the bridge, quite sure it'll be OK

Think the PCB's will be happy with that voltage, but for ecc88 "group" :  Typical Va=90Vdc and limiting Va=130Vdc, or am I misunderstanding  :thinking:

So I hit a snag :headbanger:.  Thought I'd  reuse this transformer from an old Little Dot.  Yellow  secondaries  will work for heaters but the white and the blue  secondaries measure about 9Vac each.  Thought one of them would be around 100Vac so I could use it for HT (looking at 90-130Vdc). ...

% So you'll keep the valve PCB mounting base on the original side but mount all components from underneath (the base can't be soldered on the underside as that will change pin "positions" )  :thinking: Looked again and see that's what you already did  :thumbs:

/\What Fredeb said

Checked the populated phono PCB.  I'll be using 6922's (6DJ8) for all 3 valves and all-in-one RIAA.  Connected the X3 jumpers marked "9".  So no  connections or components in Cx, C11, C12, D5, R12 (and corresponding components on R channel) and also nothing in T1,T2,T3,T4.  Does that seem...

As for power supply, again from Valvewizard: Using a combination of these 2, but without Bias Supply, (can't find the  link now).

I have a new normal size chassis left as I bought 3 some time ago from Geco/Heinrich. So it will look like the other components.  Currently toying with the idea of a perspex window on the right side of the faceplate so the pcb/valves will be visible.

Go to valvewizard.co.uk then click on 3 valve phono preamp on the right, it'll take you to this  page Then click on component flow chart bottom of same page

Also  a few questions please: 1.  Which cap is preferred as C4? 2.  C8:  10uF is physically very small.... even when compared  to 56pF :thinking: 3.  What is D5/D25?

Didn't want to start a new topic as it'll  probably just be a few posts.  Finished with 2 diameters of copper pipe as I had most materials  at hand.  Also had a roll of co-ax wire left over from a previous disc installation.  Finished according to 100Mhz measurements and managed to install it...

Found this calculator on www.hamuniverse.com [url=https://postimg.cc/1439D2Bp]

/\ :2thumbs:, Will try inside the roof first, signal quite good with basic T-shape aerial but it is too unsightly Thx

Morning, think I'm going  to do a J-pole soon.  1.  Will it be effective if positioned inside the ceiling only and not outside.  Will it then still have to be grounded? 2.  If outside: do I use surfix cable to ground  it, quite sure single core surfix doesn't exist :thinking: 3.  Is...