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Old 9th December 2010, 12:27 PM   #21
Zekk is offline Zekk  Singapore
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Thanks guy!

Whatever you suggest, be aware that I'm aiming for something around 800vdc B+.

The 0.25uf cap is firstly used in place as choke input and secondly, to cut down the final B+. I'm only guessing .. newbie!

Regarding those 816 mercury vapor rectifiers, I love the glow!
Lots of those hot shot builders out there uses 866A, so, why not jump in the bangwagon for a ride?
To be honest, I can't hear the different !

Have A Nice Day!

Zekk
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Old 9th December 2010, 01:28 PM   #22
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Hi!

If you want to use the mercury rectifiers, stick to choke input or small first cap as they are only specified for choke input filters.

I like these too. The blue glow is unbeatable. If you want to stay more conventional, use two TV damper diodes like 6AX4, 6DE4, 6AU4, 6CG3,etc. cheap and very robust (but no blue glow).

I second the recommendation to use 3 silicon diodes in series, those diodes will see very large peak inverse voltages.

You will need more LC stages to get the ripple down to acceptable levels.

Best regards

Thomas
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Old 12th December 2010, 02:51 AM   #23
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Hi, as simulated in Duncan amps PS Designer II
This will give you a voltage of around 950V. Well within the spec of the GM-70 and the voltage should come down to around 750 V with a load of around 200mA...
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Old 12th December 2010, 11:37 AM   #24
Zekk is offline Zekk  Singapore
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Default Thanks *quikie22*.

Quote:
Originally Posted by quikie22 View Post
Hi, as simulated in Duncan amps PS Designer II
This will give you a voltage of around 950V. Well within the spec of the GM-70 and the voltage should come down to around 750 V with a load of around 200mA...
Hi .... I'm indeed grateful for your desire to help-out!

Can I use IN5822 or .....?

Can I use a #83 mercury before C1 ?

Now, I can proceed with confident to build it on a breadboard.

Cheers!

Zekk
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Old 12th December 2010, 01:29 PM   #25
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do a google search for Duncan Amps PS designer 2. It runs on Windows and allows you to simulate most power supplies. You can design any power supply you want using tubes or solid state devices. :-) In fact, it would be best to do the simulations yourself as you will have the exact spec of the devices you will be using. As is, I am guesstimating the specs of your devices hence follow the recommendations of the simulator at your own risk!!.
Anyway, as requested, a #83 PS.
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Old 12th December 2010, 01:40 PM   #26
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Quote:
Originally Posted by Zekk View Post

Can I use IN5822 or .....?

Zekk
1N5822 is a low voltage Schottky diode, I think with max PIV of 40V. Not really suitable application in this circuit. Unless you wish to serialise at least 25 of them for each limb of the bridge making it a total of 100 diodes for this circuit :-D

A viable option would be serialised pair or triplet of 1N4007 or 1N5408 if you wish to use solid state rectifiers. However do not that the final voltage will be much much higher due to lower losses in the bridge. If you wish, there are also fast recovery UF4007 that can be used.
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Old 12th December 2010, 07:58 PM   #27
piano3 is offline piano3  United Kingdom
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Or 4 damper tubes which are cheap,quiet,robust,efficient and will ramp up the voltage very gradually. Remember,you will need several heater supplies if you use tubes. There is also a very tough Soviet rectifier-5C8S,of which you could use 3 for an exceeding mean looking supply-which is also cheap but it will not give you such a slow start.
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Old 15th December 2010, 12:42 AM   #28
Zekk is offline Zekk  Singapore
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A big THANK YOU to all .
Greatly appreciated it!

Zekk
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Old 15th December 2010, 01:50 AM   #29
djn is offline djn  United States
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Take this with a grain, but I've heard many times that Merq Rec tubes are noisy. Might be worth investigating.

I am using 2 6D22 damper diodes for my 650-0-650 ps
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Old 15th December 2010, 03:30 AM   #30
Zekk is offline Zekk  Singapore
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Quote:
Originally Posted by djn View Post
Take this with a grain, but I've heard many times that Merq Rec tubes are noisy. Might be worth investigating.

I am using 2 6D22 damper diodes for my 650-0-650 ps
Hi ... Ya, I've read so much about it but to my surprise, no audible noice from my SE TT21 into 101dB speakers.

You don't switched on just listening to noice alone... right?
When the music starts, the ripples and the wrinkles are smoothed out!

Mercury vapor is very addictive!
That greenish blue glow will wow you over to this danger zone!

Have fun!
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