Klystron Tuning Unit 207A - UK Vintage Radio Repair and Restoration Discussion Forum

BassoonBloke · 24th Feb 2017, 1:13 pm

Hello People,

I would like to know if anyone has any info on this unit:
http://www.tubecollector.org/equipme...-unit-207a.htm
I have one, but the power supply has been removed and I would like to try to rebuild it. Obviously a circuit diagram would also be a tad handy !!
Anyone out there able to help me as I can find nothing on the web about this lump.
Thanks very much,

Alan.

G6Tanuki · 24th Feb 2017, 2:04 pm

http://www.iwm.org.uk/collections/item/object/30005945

http://www.iwm.org.uk/collections/item/object/30117459

Part of H2S. Perhaps the IWM would have more details?

M0FYA Andy · 24th Feb 2017, 3:28 pm

Alan,
This was an interim unit used in H2S MkIIC.
In MkIIA and MkIIB, the local oscillator klystron circuit was housed in the navigator's Indicator Type 162.
For MkIIC, this indicator was replaced by the Type 184, and the LO moved into the unit you have, which was installed on the navigator's table. (Curiously, I can't recollect ever seeing a picture showing this installation).
At MkIII, the LO circuit was moved into the transmitter unit, with provision for the navigator to tune the klystron remotely.

The document you need is A.P.2890L, which I have as a 50MB pdf. I've extracted the circuit diagram, attached. Bear in mind the unit is supplied with power at 80v 1600Hz.

Andy

BassoonBloke · 24th Feb 2017, 4:42 pm

Hi Andy,

Wow that's excellent !!
Thanks very much. I was puzzling for ages what the transformer arrangement was.
Very much appreciated.

Alan.

Ed_Dinning · 25th Feb 2017, 8:10 am

Hi Alan, I have some 1600Hz transformers if required, but can also advise on 50Hz transformers if needed.

Ed

BassoonBloke · 27th Feb 2017, 12:31 pm

Hi Ed,

Thanks for the offer of help with the TX's. I must admit that I was more intrigued with the PSU circuit and layout and saw very briefly the circuit kindly supplied. Of course on a second look I realise that the power supply is for external use and not actually for the Klystron, as this seems to come from another source. All that I need is a 4V heater supply for the Klystron and then a HT supply which I think will be about 1.5KV.
I will have a muck around at some point in time and see what can be done.
Is there an easy way to detect the low level microwaves coming out of the unit (assuming that something is actually working) ?

Thanks All.
Alan.

G6Tanuki · 27th Feb 2017, 3:01 pm

Quote:

Originally Posted by BassoonBloke

Is there an easy way to detect the low level microwaves coming out of the unit (assuming that something is actually working) ?

You used to be able to buy - rather cheaply - "Microwave Oven leakage meters". This was back in the days when a certain section of society had the strange idea that microwave-ovens and anything else involving 'radiation' was likely to cause your kids to sprout a second head and your cat to gain enough intelligence to leave home and start up a small industrial business in the West Midlands.

The meters were a 'butterfly' pf PCB material as a 1/2-wave dipole cut to resonate at 2.45MHz, with a diode and small moving-coil meter across the feedpoint.

Seems they're still available: even with a well-stocked junkbox I doubt you could build your own cheaper than you can buy one from Maplin! http://www.maplin.co.uk/p/microwave-...n-tester-n53fu

BassoonBloke · 28th Feb 2017, 1:52 pm

Hi,

Great stuff, thanks for that. I guess I could splash out a fiver for one of those !!

I'll let you know how I get along, when I get around to having a bit of an experiment.

Cheers,
Alan.

24th Feb 2017, 1:13 pm	#1
BassoonBloke Pentode Join Date: Feb 2006 Location: East London, UK. Posts: 231	Klystron Tuning Unit 207A Hello People, I would like to know if anyone has any info on this unit: http://www.tubecollector.org/equipme...-unit-207a.htm I have one, but the power supply has been removed and I would like to try to rebuild it. Obviously a circuit diagram would also be a tad handy !! Anyone out there able to help me as I can find nothing on the web about this lump. Thanks very much, Alan.

24th Feb 2017, 2:04 pm	#2
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,998	Re: Klystron Tuning Unit 207A http://www.iwm.org.uk/collections/item/object/30005945 http://www.iwm.org.uk/collections/item/object/30117459 Part of H2S. Perhaps the IWM would have more details?

24th Feb 2017, 4:42 pm	#4
BassoonBloke Pentode Join Date: Feb 2006 Location: East London, UK. Posts: 231	Re: Klystron Tuning Unit 207A Hi Andy, Wow that's excellent !! Thanks very much. I was puzzling for ages what the transformer arrangement was. Very much appreciated. Alan.

25th Feb 2017, 8:10 am	#5
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: Klystron Tuning Unit 207A Hi Alan, I have some 1600Hz transformers if required, but can also advise on 50Hz transformers if needed. Ed

27th Feb 2017, 12:31 pm	#6
BassoonBloke Pentode Join Date: Feb 2006 Location: East London, UK. Posts: 231	Re: Klystron Tuning Unit 207A Hi Ed, Thanks for the offer of help with the TX's. I must admit that I was more intrigued with the PSU circuit and layout and saw very briefly the circuit kindly supplied. Of course on a second look I realise that the power supply is for external use and not actually for the Klystron, as this seems to come from another source. All that I need is a 4V heater supply for the Klystron and then a HT supply which I think will be about 1.5KV. I will have a muck around at some point in time and see what can be done. Is there an easy way to detect the low level microwaves coming out of the unit (assuming that something is actually working) ? Thanks All. Alan.

28th Feb 2017, 1:52 pm	#8
BassoonBloke Pentode Join Date: Feb 2006 Location: East London, UK. Posts: 231	Re: Klystron Tuning Unit 207A Hi, Great stuff, thanks for that. I guess I could splash out a fiver for one of those !! I'll let you know how I get along, when I get around to having a bit of an experiment. Cheers, Alan.