Military PX4 (Holy Grail??) - UK Vintage Radio Repair and Restoration Discussion Forum

HamishBoxer · 1st Nov 2010, 9:00 pm

Was there ever a military version of the above? The reason for asking is i have 3 balloon CV243 (4045A) valves,which look very similar.5 pin bases,and wondered as i can find very little on these if they are a millitary version.Certainly not listed as equivalent so dont no.Guess if i am correct they will be worth serious cash!

Thanks David

vinrads · 1st Nov 2010, 9:05 pm

Try Google there is some info could interest you.

Top Cap · 1st Nov 2010, 9:11 pm

http://www.tubecollector.org/4045a.htm

Its a Tetrode.

HamishBoxer · 1st Nov 2010, 9:13 pm

Spot on Top Cap,thats the boy ok! Thanks to all other replies.

Regards David

HamishBoxer · 1st Nov 2010, 9:19 pm

Seems these are audio grade and used in audio telephone repeaters according to whats being sold on ebay.Quite rare if i understand right.

David

Herald1360 · 2nd Nov 2010, 1:34 pm

There seems to be a fair bit of info in Frank's electron tube pages.....

http://frank.pocnet.net/sheets/144/4/4A-137B.pdf

plus a GPO spec as well (start looking for CV243).

It doesn't seem to be a particularly powerful valve, but there are some data suggesting that it will deliver about 5W with 250V on the anode, which would suggest an anode dissipation rating of around 10W.

In fact apart from the details it would seem to be fairly similar in capabilities to a 6V6.

HamishBoxer · 2nd Nov 2010, 1:50 pm

Thank You Herald for that,yes they are marked CV243.Shame not PX4s!

Regards David

1st Nov 2010, 9:00 pm	#1
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Military PX4 (Holy Grail??) Was there ever a military version of the above? The reason for asking is i have 3 balloon CV243 (4045A) valves,which look very similar.5 pin bases,and wondered as i can find very little on these if they are a millitary version.Certainly not listed as equivalent so dont no.Guess if i am correct they will be worth serious cash! Thanks David

1st Nov 2010, 9:05 pm	#2
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Military PX4 (Holy Grail??) Try Google there is some info could interest you.

1st Nov 2010, 9:11 pm	#3
Top Cap Octode Join Date: Mar 2006 Location: Watford, Hertfordshire, UK. Posts: 1,270	Re: Military PX4 (Holy Grail??) http://www.tubecollector.org/4045a.htm Its a Tetrode. __________________ Whether the Top Cap is Grid or Anode - touching it will give you a buzz either way!

1st Nov 2010, 9:13 pm	#4
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Military PX4 (Holy Grail??) Spot on Top Cap,thats the boy ok! Thanks to all other replies. Regards David

1st Nov 2010, 9:19 pm	#5
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Military PX4 (Holy Grail??) Seems these are audio grade and used in audio telephone repeaters according to whats being sold on ebay.Quite rare if i understand right. David

2nd Nov 2010, 1:34 pm	#6
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Military PX4 (Holy Grail??) There seems to be a fair bit of info in Frank's electron tube pages..... http://frank.pocnet.net/sheets/144/4/4A-137B.pdf plus a GPO spec as well (start looking for CV243). It doesn't seem to be a particularly powerful valve, but there are some data suggesting that it will deliver about 5W with 250V on the anode, which would suggest an anode dissipation rating of around 10W. In fact apart from the details it would seem to be fairly similar in capabilities to a 6V6. __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

2nd Nov 2010, 1:50 pm	#7
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Military PX4 (Holy Grail??) Thank You Herald for that,yes they are marked CV243.Shame not PX4s! Regards David