833A (GU-48) Amp

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Nick
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#1186 Re: 833A (GU-48) Amp

Post by Nick »

So if anyone had a dip in their electricity supply about 5:30 pm, it was me.
A whole 100W...
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pre65
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#1187 Re: 833A (GU-48) Amp

Post by pre65 »

Nick wrote: ↑Mon Jul 20, 2020 6:28 pm
So if anyone had a dip in their electricity supply about 5:30 pm, it was me.
A whole 100W...
Humour is not my strong point. :oops:
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Ray P
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#1188 Re: 833A (GU-48) Amp

Post by Ray P »

Nick wrote: ↑Mon Jul 20, 2020 6:28 pm
So if anyone had a dip in their electricity supply about 5:30 pm, it was me.
A whole 100W...
Returned to work today after a week off - I think I can account for around 100 'whats'!
Sorry, I couldn't resist!
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Paul Barker
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#1189 Re: 833A (GU-48) Amp

Post by Paul Barker »

pre65 wrote: ↑Tue May 19, 2020 3:56 pm I have a feeling that the two E chokes I have were "fried" in an unfortunate misconnection event many years ago, So I've purchased two more from our Greg, who had some unused ones in hand.
Shorted secondary?
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pre65
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#1190 Re: 833A (GU-48) Amp

Post by pre65 »

Paul Barker wrote: ↑Mon Jul 20, 2020 6:58 pm
pre65 wrote: ↑Tue May 19, 2020 3:56 pm I have a feeling that the two E chokes I have were "fried" in an unfortunate misconnection event many years ago, So I've purchased two more from our Greg, who had some unused ones in hand.
Shorted secondary?
Not quite Paul.

They were on my dual mono power supply and there was a "connection error" with my 811a amp. :oops:
The only thing necessary for the triumph of evil is for good men to do nothing.

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pre65
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#1191 Re: 833A (GU-48) Amp

Post by pre65 »

The second unit has now been switched on for the filament test, much the same as the other one, just needed a gnats more voltage to allow for the filament choke.

I was going to wait till morning, but I had a short burst of enthusiasm. :shock:

After today the real work begins, power supply. The diode boards I made originally for these amps, currently reside on the GK-71 amps, but rather than make two more I'll nick them back again. That will save me some time. :)
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pre65
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#1192 Re: 833A (GU-48) Amp

Post by pre65 »

This is an old picture from years ago when I built the first iteration, but it shows what the GU48 looks like lit up. :)

Image
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Paul Barker
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#1193 Re: 833A (GU-48) Amp

Post by Paul Barker »

beauty personified
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
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IslandPink
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#1194 Re: 833A (GU-48) Amp

Post by IslandPink »

This is a very worthwhile project !
"Once you find out ... the Circumstances ; then you can go out"
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Paul Barker
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#1195 Re: 833A (GU-48) Amp

Post by Paul Barker »

Yes great bottles.
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pre65
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#1196 Re: 833A (GU-48) Amp

Post by pre65 »

I don't know if the 833a amp that our man in Bedford built is still serviceable ?
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andrew Ivimey
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#1197 Re: 833A (GU-48) Amp

Post by andrew Ivimey »

Ha! I've gone all green power with cheap chinese ampus digitalis but oh, how I miss the glow. I used a couple of amps to drive the 833s rather like Darren.
Philosophers have only interpreted the world - the point, however, is to change it. No it isn't ... maybe we should leave it alone for a while.
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pre65
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#1198 Re: 833A (GU-48) Amp

Post by pre65 »

andrew Ivimey wrote: ↑Tue Jul 21, 2020 12:42 pm I used a couple of amps to drive the 833s rather like Darren.
As did I, and still will for the time being.

Has anyone had any contact with Darren ? He was my inspiration for this amp. :)
The only thing necessary for the triumph of evil is for good men to do nothing.

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Paul Barker
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#1199 Re: 833A (GU-48) Amp

Post by Paul Barker »

I last spoke to him on the phone some years ago. At which time all was well in his life after his former active involvement in slatedeck et al, he had evolved into an active country life involving tractors collies sheep so on and so forth. We last spoke as good friends but haven’t either of us felt the need to affirm our situation with regular phone calls. But in a crisis both know the other would be on the end of the line.
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pre65
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#1200 Re: 833A (GU-48) Amp

Post by pre65 »

I've done a little bit more, the mains transformer is mounted, as is the choke, and the two PSU capacitors.

Just needs the diode board fitting, and the wires connecting up now, which will have to be Saturday as Friday is a Mum day.
The only thing necessary for the triumph of evil is for good men to do nothing.

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