Search found 747 matches

by RhythMick
Sat Jan 14, 2023 7:38 pm
Forum: Everyones Projects
Topic: Help before I lose my sanity
Replies: 17
Views: 8220

Re: Help before I lose my sanity

Nick wrote: Sat Jan 14, 2023 7:31 pm Did the fuse go on the wind up from 0?
I'll repeat the test. I may have only done the wind up with heaters only, which was successful.
by RhythMick
Sat Jan 14, 2023 6:51 pm
Forum: Everyones Projects
Topic: Help before I lose my sanity
Replies: 17
Views: 8220

Re: Help before I lose my sanity

Nick wrote: Sat Jan 14, 2023 6:25 pm Are you winding the Variac up from 0 or just turning on when set to 240v?
Hmmm... First time I wound up from zero. Repeat tests I just switched on.
by RhythMick
Sat Jan 14, 2023 6:37 pm
Forum: Everyones Projects
Topic: Help before I lose my sanity
Replies: 17
Views: 8220

Re: Help before I lose my sanity

not sure this is related to your problem..but...cap input for 5R4WGB is max at 4uf Thanks Ed yes I saw that. Also the transformer DC resistance is lower than spec. Inrush current? The Variac fuse is 2A slo blo. However, as I say only the 5V winding should have current through it. The 325-0-325 wind...
by RhythMick
Sat Jan 14, 2023 5:38 pm
Forum: Everyones Projects
Topic: Help before I lose my sanity
Replies: 17
Views: 8220

Re: Help before I lose my sanity

With the rectifier tube removed, measuring resistance from pin 2 to the ground bus shows 75K (after the current from the multimeter charges up the caps it settles at 75K). Obviously it's connected through the transformer winding to pin 8 and on through the CLC.
by RhythMick
Sat Jan 14, 2023 5:26 pm
Forum: Everyones Projects
Topic: Help before I lose my sanity
Replies: 17
Views: 8220

Help before I lose my sanity

... though some might say it's too late. A friend and I have discussed building a guitar amp and though I've only built hifi amps before we've started to develop a prototype. Really simple, starting with SE similar to Fender Champ 5F1 but with some of the crap parts of the design amended (no death c...
by RhythMick
Sun Jan 01, 2023 5:59 pm
Forum: Everyones Projects
Topic: Douglas Self Phono Stage
Replies: 5
Views: 4910

Re: Douglas Self Phono Stage

I would consider using good quality metal braiding around the umbilical, earthing one end - I would be inclined to ground the shield at the PSU end, effectively making the shield an extension of the (presumably metal) PSU case. What umbilical connectors are you using? Metal or plastic? There will I'...
by RhythMick
Sun Sep 18, 2022 6:41 pm
Forum: Everyones Projects
Topic: 45 SET
Replies: 134
Views: 29626

Re: 45 SET

Nick wrote: Fri Aug 26, 2022 9:09 am
Ali Tait wrote: Fri Aug 26, 2022 8:54 am No right one Simon. :D
That was Naked Gun. Just saying.

That clip still makes me spit my tea...
by RhythMick
Sun Aug 07, 2022 12:16 pm
Forum: Everyones Projects
Topic: Filament Bias and supplies
Replies: 2
Views: 3052

Re: Filament Bias and supplies

Ok I think I'll... Remove the caps and diodes from the boards, bridging from inputs to cap +/- Put the transformer, diodes and caps in the off board PSU box Use an 01A PSU feeding 2 boards at 0.25A each Use a 71A PSU feeding 1 boards at 0.25A each Works out nicely using 50VA toroids 2x12v I have in ...
by RhythMick
Sun Aug 07, 2022 10:13 am
Forum: Everyones Projects
Topic: Filament Bias and supplies
Replies: 2
Views: 3052

Re: Filament Bias and supplies

Just re-read Andrew's introductory post on the DC boards and the caps would need to be higher voltage than the default. Off to check what I installed.
by RhythMick
Sun Aug 07, 2022 9:48 am
Forum: Everyones Projects
Topic: 112a driver stage.
Replies: 13
Views: 7350

Re: 112a driver stage.

Not yet, seems to be on back order with my supplier. :lol: Mind you, I do have LOTS of other things to do in the summer, this month alone I've got 2 coach trips, one steam train day trip, walking group twice a week and more than enough outdoor bowls matches to keep me occupied. :D Sounds like a lif...
by RhythMick
Sun Aug 07, 2022 9:20 am
Forum: Everyones Projects
Topic: Filament Bias and supplies
Replies: 2
Views: 3052

Filament Bias and supplies

In a fit of enthusiasm I decided I'd like to experiment with filament bias. I'd like to make sure I've got my head properly around the supply requirements. In particular looking at the 01A and 71A valves. Both are Vf = 5v If = 0.25A Starting with the 01A, aiming for Vg = 7.5v and Ia = 3mA, so Rfil =...
by RhythMick
Sun Aug 07, 2022 8:46 am
Forum: Everyones Projects
Topic: 112a driver stage.
Replies: 13
Views: 7350

Re: 112a driver stage.

Did the bout of enthusiasm appear...?

Watching with interest...
by RhythMick
Sun Jul 10, 2022 6:02 pm
Forum: Everyones Projects
Topic: Anyone up for a listen to my system?
Replies: 2
Views: 2643

Re: Anyone up for a listen to my system?

Id like and look forward to a daytime visit but not the sleep over as Im a very light drinker barely half a pint a quater of a year, and one of those is owston. Commitments allowing. Daytime works fine for me. See how many others we get. Friday, Saturday or Sunday for me, but I'm guessing most will...
by RhythMick
Sat Jul 09, 2022 6:06 pm
Forum: Everyones Projects
Topic: Anyone up for a listen to my system?
Replies: 2
Views: 2643

Anyone up for a listen to my system?

Been a while since I posted, mostly due to work pressures. However I have a) gone down to a 4-day week and b) set a date for retirement. Ok I have another year to go but now work is about lining up successors rather than being at the coalface myself. So I have a little time to relax occasionally. Al...
by RhythMick
Fri Oct 22, 2021 8:56 am
Forum: Everyones Projects
Topic: Poundland 45
Replies: 160
Views: 34759

Re: Poundland 45

Is it worth adding fuses to each transformer secondary?

You could also off board the power supply into a separate chassis with an umbilical if the chassis is tight, though it sounds like you don't need it now. I usually find the power supply dominates the space requirements.