PSU for valves

Peter

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Feb 17, 2021, 11:52:15 AM2/17/21

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I thought I'd experiment with a few valve circuits (just for fun). So
I'll need an H.T. power supply and I'm looking at this:
https://www.timstar.co.uk/el120300-high-tension-ht-power-supply.html
It supplies up to 300V at 60mA. My question is, is 60mA sufficient?
--
When, once, reference was made to a statesman almost universally
recognized as one of the villains of this century, in order to
induce him to a negative judgment, he replied: "My situation is
so different from his, that it is not for me to pass judgment".
Ernst Specker on Paul Bernays

RheillyPhoull

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Feb 17, 2021, 5:05:20 PM2/17/21

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On 18/02/2021 12:51 am, Peter wrote:
> I thought I'd experiment with a few valve circuits (just for fun). So
> I'll need an H.T. power supply and I'm looking at this:
> https://www.timstar.co.uk/el120300-high-tension-ht-power-supply.html
> It supplies up to 300V at 60mA. My question is, is 60mA sufficient?

Probably Ok for pre-amp valves but not for power amps.

Phil Allison

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Feb 17, 2021, 5:42:46 PM2/17/21

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Peter wrote:
------------------

> I thought I'd experiment with a few valve circuits (just for fun). So
> I'll need an H.T. power supply and I'm looking at this:
>
> https://www.timstar.co.uk/el120300-high-tension-ht-power-supply.html
> It supplies up to 300V at 60mA. My question is, is 60mA sufficient?
> -

** That is clearly a regulated lab supply for experiments in physics.
Major overkill for playing about with tube circuits.
Expensive too.

...... Phil

Peter

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Feb 17, 2021, 8:23:35 PM2/17/21

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Can you recommend an alternative?

> ...... Phil

Phil Allison

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Feb 17, 2021, 10:08:37 PM2/17/21

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Peter wrote:
============

> > ** That is clearly a regulated lab supply for experiments in physics.
> > Major overkill for playing about with tube circuits.
> > Expensive too.
> Can you recommend an alternative?
>

** FSS build something - takes about one hour of time

One transformer, one bridge rectifier and one or two electros.
Get yourself a Variac too.
You can run heaters on a 6V battery.

If you cannot manage that, you have no place fiddling with tube circuits.

...... Phil

RheillyPhoull

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Feb 18, 2021, 6:55:10 PM2/18/21

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On 18/02/2021 9:23 am, Peter wrote:
> Phil Allison wrote:
>> Peter wrote:
>> ------------------
>>> I thought I'd experiment with a few valve circuits (just for fun). So
>>> I'll need an H.T. power supply and I'm looking at this:
>>>
>>> https://www.timstar.co.uk/el120300-high-tension-ht-power-supply.html
>>> It supplies up to 300V at 60mA. My question is, is 60mA sufficient?
>>> -
>>
>> ** That is clearly a regulated lab supply for experiments in physics.
>>      Major overkill for playing about with tube circuits.
>>      Expensive too.
>
> Can you recommend an alternative?
>
>> ......   Phil
>>
>
>

Hey Pete,
Read this one <http://education.lenardaudio.com/en/14_valve_amps_6.html>

Phil Allison

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Feb 18, 2021, 7:13:00 PM2/18/21

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RheillyPhoull wrote:

============

>
>> Read this one <http://education.lenardaudio.com/en/14_valve_amps_6.html>

** Then forget it.

Even worse overkill than the lab supply.

.... Phil

RheillyPhoull

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Feb 19, 2021, 2:46:34 AM2/19/21

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You're such a bugger when you criticize Phil :-)

Phil Allison

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Feb 19, 2021, 3:16:35 AM2/19/21

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RheillyPhoull wrote:
====================

>>
> >>> Read this one <http://education.lenardaudio.com/en/14_valve_amps_6.html>
> >
> > ** Then forget it.
> >
> > Even worse overkill than the lab supply.
> >

> >

> You're such a bugger when you criticize Phil :-)

** ...... ;-0

..... Phil

Peter

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Feb 19, 2021, 11:57:07 AM2/19/21

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Thank you. That's really helpful. Looking at the first circuit
diagram, any thoughts about the value of the pi filter choke? Also,
looking at the second circuit diagram, the swinging choke is marked 20H,
but the smoothing choke has no value given. Any thought about that?

Peter

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Feb 19, 2021, 11:59:05 AM2/19/21

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But I'll have the fun (let's hope) of building it myself.

Phil Allison

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Feb 19, 2021, 4:10:06 PM2/19/21

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On Saturday, February 20, 2021 at 3:59:05 AM UTC+11, Peter wrote:
> Phil Allison wrote:
> > RheillyPhoull wrote:
> >
> > ============
> >>
> >>> Read this one <http://education.lenardaudio.com/en/14_valve_amps_6.html>
> >
> > ** Then forget it.
> >
> > Even worse overkill than the lab supply.
> But I'll have the fun (let's hope) of building it myself.

** Building what ?

Did you even read the page at all ?

The author is Australian and known to me, he has long history of being a crank.

So you have a pal.

..... Phil

Peter

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Feb 23, 2021, 5:09:48 AM2/23/21

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Peter wrote:
> RheillyPhoull wrote:
>> On 18/02/2021 9:23 am, Peter wrote:
>>> Phil Allison wrote:
>>>> Peter wrote:
>>>> ------------------
>>>>> I thought I'd experiment with a few valve circuits (just for fun). So
>>>>> I'll need an H.T. power supply and I'm looking at this:
>>>>>
>>>>> https://www.timstar.co.uk/el120300-high-tension-ht-power-supply.html
>>>>> It supplies up to 300V at 60mA. My question is, is 60mA sufficient?
>>>>> -
>>>>
>>>> ** That is clearly a regulated lab supply for experiments in physics.
>>>>      Major overkill for playing about with tube circuits.
>>>>      Expensive too.
>>>
>>> Can you recommend an alternative?
>>>
>>>> ......   Phil
>>>>
>>>
>>>
>> Hey Pete,
>> Read this one <http://education.lenardaudio.com/en/14_valve_amps_6.html>
>
> Thank you. That's really helpful. Looking at the first circuit
> diagram, any thoughts about the value of the pi filter choke? Also,
> looking at the second circuit diagram, the swinging choke is marked 20H,
> but the smoothing choke has no value given. Any thought about that?
>

Thank you for your email. I tried to reply to it, but my reply bounced.