[ARC5] 1625 question

[Robert Downs]

The absolute max rated voltage given in the tube manuals is the DC output voltage of the power supply.  And includes a safety factor plus assumes that at that voltage, the peak voltage on the plates is going to be 1500 volts.  So operating the tubes with 1000 VDC on the plates depends upon “using” some or most of that safety factor.  

 

Robert Downs - Houston

WA5CAB

 

Sent: Tuesday, 6 February 2018 12:07 PM
To: ARC5 at mailman.qth.net
Subject: [ARC5] 1625 question

 

I am reading some old surplus manuals and find that they like to use the 1625/807 as a power amplifier ( typical ARC-5 parallel style ) and suggest that one could run up to 1000 volts on the plate. Every listing I can find shows a absolute maximum plate voltage for the 1625 of 750 volts. Yes, the operating plate voltage will depend upon class of service and therefor duty cycle but isn’t absolute maximum absolute maximum? Now I can remember pushing the stated maximums a bit and I even have a friend who admits running a tube in a coffee can full of water to get a few more watts out of it.  But none of it was “published” that I know of. What am I missing?

 

 

Ron K3PID

 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20180206/57bd2919/attachment.html>