Re: PM Tubes (fwd)

["High Voltage list" <hvlist@xxxxxxxxxx>]

Original poster: Steven Roys <sroys@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Wed, 12 Dec 2007 16:29:25 -0800
From: Ed Phillips <evp@xxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: PM Tubes (fwd)

High Voltage list wrote:

>Original poster: Steven Roys <sroys@xxxxxxxxxx>
>
>
>
>---------- Forwarded message ----------
>Date: Mon, 10 Dec 2007 23:09:29 -0800
>From: Dave Halliday <dh@xxxxxxxxxxxxxx>
>To: 'High Voltage list' <hvlist@xxxxxxxxxx>
>Subject: RE: PM Tubes (fwd)
>
>And also, do not apply power to it while it is in the light.  This can cause
>a meltdown of the dynodes.  For some of these puppies, full-signal is
>measured in hundreds of photons/second.
>
>Dave 
>
>  
>
>> <>-----Original Message-----
>> From: High Voltage list [mailto:hvlist@xxxxxxxxxx]
>> Sent: Monday, December 10, 2007 5:42 PM
>> To: hvlist
>> Subject: RE: PM Tubes (fwd)
>>
>> Original poster: Steven Roys <sroys@xxxxxxxxxx>
>>
>>
>>
>> ---------- Forwarded message ----------
>> Date: Mon, 10 Dec 2007 08:59:34 -0500
>> From: Richard Hull <hullr@xxxxxxxxxxxx>
>> To: High Voltage list <hvlist@xxxxxxxxxx>
>> Subject: RE: PM Tubes (fwd)
>>
>> The sockets for these are critical and contian a resistor
>> divider string to distribute the high voltage and bias the
>> many dynodes. Without this key component or without a proper
>> pin out, you are stuck. The voltage requirements are usually
>> 1000 volts at the end of the dynode string. A socket might
>> have as many as 10 resistors on it and 3 or 4 capacitors.
>>
>> While the basing of most 8 and 10 dynode tubes is similar, a
>> wrong move or connection could damage the tube. Most tubes
>> have 12 to 16 pins with 14 being the most common.
>>
>> Richard Hull
>
    Without the schematic of the socket the whole subject is kind of 
meaningless but it's easy enough to arrange the voltage divider from 
small carbon film resistors soldered to the socket [if one has the 
socket].  Real issue is base connections and I can't help.

Ed