Two Hewlett-Packard 540B Transfer Oscillators FOC - UK Vintage Radio Repair and Restoration Discussion Forum

Anthony · 25th Nov 2020, 2:00 pm

I have 2 of these surplus to requirements. They have not been out of warm, dry, storage for several years but were fully operational. I know that one lacks a signal input plug but both are in excellent cosmetic condition. They are beautifully-made and unmolested AFAIK. If there is any interest I shall pull them from storage and check them. Please let me know of any interest (non-binding).

mickm3for · 25th Nov 2020, 3:13 pm

Hi i would be intrested if posting is an option .
they are usefull for frequency mesurments
ie A transfer oscillator, somewhat like a frequency counter prescaler, allows you to read frequencies far beyond the range of the counter you are using it with, well into the microwave region, 12.5 Gigahertz without the associated mixer. with the mixer it is extended to 18 GHZ.

It was designed to be used with the ancient model HP524, a 10 Mhz counter from the 50's.

factory · 25th Nov 2020, 3:51 pm

Also interested, the 540B model could also be used with the 5243L (which I have one of in my collection), not yet found an earlier 524 series.

David

Eddystone · 25th Nov 2020, 4:05 pm

Just for interest...

So is this an "injection locked oscillator" type thing which locks to a subharmonic of the incoming signal?

Regards,

Rob

EDIT: Answered my own question with a bit of Googling. No it uses a proper PLL approach:

http://www.leapsecond.com/pdf/an200-1.pdf

Anthony · 25th Nov 2020, 7:14 pm

There is some interest so I shall dig them out in the next week.

Buzby123 · 25th Nov 2020, 8:35 pm

This, I think, is instruction manual for the US military version ...

http://bama.edebris.com/download/hp/540b/HP%20540B.pdf

Scroll down past all the army talk, and you should see your 540B and some instructions.

Cheers,

Buzby

25th Nov 2020, 2:00 pm	#1
Anthony Pentode Join Date: Sep 2006 Location: Hertford, Herts. UK. Posts: 215	Two Hewlett-Packard 540B Transfer Oscillators FOC I have 2 of these surplus to requirements. They have not been out of warm, dry, storage for several years but were fully operational. I know that one lacks a signal input plug but both are in excellent cosmetic condition. They are beautifully-made and unmolested AFAIK. If there is any interest I shall pull them from storage and check them. Please let me know of any interest (non-binding).

25th Nov 2020, 3:13 pm	#2
mickm3for Hexode Join Date: May 2015 Location: Chatham, Kent, UK. Posts: 394	Re: Two Hewlett-Packard 540B Transfer Oscillators FOC Hi i would be intrested if posting is an option . they are usefull for frequency mesurments ie A transfer oscillator, somewhat like a frequency counter prescaler, allows you to read frequencies far beyond the range of the counter you are using it with, well into the microwave region, 12.5 Gigahertz without the associated mixer. with the mixer it is extended to 18 GHZ. It was designed to be used with the ancient model HP524, a 10 Mhz counter from the 50's.

25th Nov 2020, 3:51 pm	#3
factory Heptode Join Date: Jul 2009 Location: Cheshire, UK. Posts: 712	Re: Two Hewlett-Packard 540B Transfer Oscillators FOC Also interested, the 540B model could also be used with the 5243L (which I have one of in my collection), not yet found an earlier 524 series. David

25th Nov 2020, 4:05 pm	#4
Eddystone Triode Join Date: Dec 2011 Location: Fareham, Hampshire, UK. Posts: 22	Re: Two Hewlett-Packard 540B Transfer Oscillators FOC Just for interest... So is this an "injection locked oscillator" type thing which locks to a subharmonic of the incoming signal? Regards, Rob EDIT: Answered my own question with a bit of Googling. No it uses a proper PLL approach: http://www.leapsecond.com/pdf/an200-1.pdf Last edited by Eddystone; 25th Nov 2020 at 4:10 pm.

25th Nov 2020, 7:14 pm	#5
Anthony Pentode Join Date: Sep 2006 Location: Hertford, Herts. UK. Posts: 215	Re: Two Hewlett-Packard 540B Transfer Oscillators FOC There is some interest so I shall dig them out in the next week.

25th Nov 2020, 8:35 pm	#6
Buzby123 Pentode Join Date: Oct 2011 Location: Culcheth, Cheshire, UK. Posts: 181	Re: Two Hewlett-Packard 540B Transfer Oscillators FOC This, I think, is instruction manual for the US military version ... http://bama.edebris.com/download/hp/540b/HP%20540B.pdf Scroll down past all the army talk, and you should see your 540B and some instructions. Cheers, Buzby