HT, CT, Common, 0V... PT Wiring questions

[gtomax]

Greetings from power supply town! Had a couple of questions on the PT and just wanted to verify the following:

For the HT fuse, what does HT stand for? High Tension? Heater Tap? Is HT different from CT (Center Tap)?

My PT is a Marstran 1204-43 with wiring diagram:



So G and I are heater leads at 3.15V each that go to the tubes. H goes to ground on output valve V7.

B and D go to diode full wave rectifier as I'm using the 490VDC taps.

C is HT that goes to ground on a tranny bolt?

F is common which gets wired to the AC neutral (white) wire through the HT fuse. Also, one leg of 120V indicator lamp goes to common terminal on PT.

Brown 120V wire goes to power switch (same pole as other leg of indicator lamp) with the opposite pole going to side tap of mains fuse, end of mains fuse to AC line (black).

Sound correct? Did I miss anything?

[Flames1950]

I think you've about covered it. I don't think I'd ground H at an output tube socket though. I usually ground both H and C on the same tranny bolt for this amp. (C usually goes to the HT "high tension" fuse and then to ground incidentally, the mains AC does not run to the HT fuse.) So your white neutral AC goes straight to the F terminal.

[gtomax]

Thanks Andy... one question about the grounding:

So mains earth will connect on its own lug bolted directly to chassis. Heater ground and HT ground (H and C (after fuse)) are to be connected to their own lug near the HT fuse also bolted directly to the chassis. I don't have a ground lug that is large enough to fit over the PT mounting bolt... as long as H and C are together near the HT fuse (also near PT) will that do?

[Flames1950]

I usually use eyelets that will fit over the PT bolts (you can get them at the auto parts store or even most hardware stores anymore.) But something close that will take a ground lug will be fine too.