I have 2 transformers that could work - Which do you think would be better?
Both are not ideal - the potted one is a little shy on voltage, the Hammond has no filament CT...
I just noticed this about the potted one - if you look at the schematic, and the pins confirm it as well, the CT of the HV and the filament is the case... That's weird...
Both are not ideal - the potted one is a little shy on voltage, the Hammond has no filament CT...
I just noticed this about the potted one - if you look at the schematic, and the pins confirm it as well, the CT of the HV and the filament is the case... That's weird...
Last edited:
And the fact that the CT of the HV and FIL windings is that same shield is no problem? I ask only because I haven't seen that before.
Im needing to make one more order to get all the parts...the local electronics surplus has most of the stuff, but I still need to fill it out.
A couple questions,
What voltage NE-2? I'm not sure if the ratings are the strike voltage or max operating...
Is there any issue using a stepped attenuator? I have a 100K noble that I'm planning on using, but I'm still curious...
Are there any 'gotchas' in building this? Anything not obvious?
A couple questions,
What voltage NE-2? I'm not sure if the ratings are the strike voltage or max operating...
Is there any issue using a stepped attenuator? I have a 100K noble that I'm planning on using, but I'm still curious...
Are there any 'gotchas' in building this? Anything not obvious?
I have another question that I just cant get my head around...
When running a F4 as mono you get 50W from a single-ended connection, but 100W from a balanced. The Rails are not any higher, and you have the same amount of PSU, so how can you get a doubling of power?
I'm sure with a good explanation it will become obvious...
When running a F4 as mono you get 50W from a single-ended connection, but 100W from a balanced. The Rails are not any higher, and you have the same amount of PSU, so how can you get a doubling of power?
I'm sure with a good explanation it will become obvious...
I have another question that I just cant get my head around...
When running a F4 as mono you get 50W from a single-ended connection, but 100W from a balanced. The Rails are not any higher, and you have the same amount of PSU, so how can you get a doubling of power?
I'm sure with a good explanation it will become obvious...
You just about double the voltage swing at the output.
I finally got some tube sockets and a couple other little things to finish stuffin the PCB, and am quite close to attaching it to a piece of wood, um... I mean installing it into the testing and analysis fixture, and lighting this candle.
I am confused by a few things and could use a little clarification -
There is only one output on the regulator PCB...
But two HV inputs, and grounds, on the amp board... ??
Also, what's that little jumper for? These seem to be a revised board and I have never seen any info on them...
Attach heaters here, but still take the heater CT to the PSU board?
Anything else worth mentioning before applying power?
I am confused by a few things and could use a little clarification -
There is only one output on the regulator PCB...
But two HV inputs, and grounds, on the amp board... ??
Also, what's that little jumper for? These seem to be a revised board and I have never seen any info on them...
Attach heaters here, but still take the heater CT to the PSU board?
Anything else worth mentioning before applying power?
1) There are 2 HV inputs -- for you to regulate the 2 halves separately if you want. You'd need 2 Maida pcbs for this option. I use only one and the 2 HV nodes on the preamp board are tied together.
2) The jumper is there if you want to connect the shield of the tube to ground. Mine is open
3) Yupp, heaters go there -- twist the wires together.
4) I have C1 and C10 jumpered. I didn't find that playing with values benefitted much.
2) The jumper is there if you want to connect the shield of the tube to ground. Mine is open
3) Yupp, heaters go there -- twist the wires together.
4) I have C1 and C10 jumpered. I didn't find that playing with values benefitted much.