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Frequency range of HP 5352B frequency counter
I don't know if I've been stupid or not. I see a 40 GHz 5352B counter on eBay for ?200 (GBP). Bid on it and won it. https://order.ebay.co.uk/ord/show?itemId=165492446615 The only thing I am puzzled
By Dr. David Kirkby, Kirkby Microwave Ltd · #126536 ·
HP 3465A offset when input shorted
Hi all, Just obtained a rather sick HP3465A (the 4.5 digit one, not the big 6.5 digit unit). It is functioning but there is a one sided offset on measurements which is proportional to the
By Chris Smith <me@...> · #126535 ·
Anyone tried using a CW syntesizer as frequency marker with 8510C?
Greetings forum, A synthesized sweeper is unfortunately beyond financial reach but a cw-only synthesizer is. I have been using my 8510C with an 8350B + a 2-20GHz plug-in. It would be nice however, if
By Ulf Kylenfall · #126534 ·
Re: HP 8640B stiff main tuning
Hello we have three 8640, with varying amounts of shaft resistance, but all are OK to use. I suggest that position the gen panel up, then apply alcohol or degreaser on the shaft to flush out
By Froggie the Gremlin · #126533 ·
Re: HP 8640B stiff main tuning
Thanks for all the suggestions. I have been able to clean off the grease residue on the other bearings which are accessible for disassembly using isopropyl alcohol. The problem with cleaning the
By mondial · #126532 ·
Re: HP 3456A Repair help needed
As an observation: Any time the presence or absence of a measurement probe (scope, meter, etc) makes a difference, you're dealing with a marginal situation. Your probe represents at least a
By Harvey White · #126531 ·
Re: HP 3456A Repair help needed
-------- Hi John, Great news and congratulations for the repair. You already debugged it 99% of the way by identifying 1M-ohm from gate to ground makes a difference. That 100k resistor is not carrying
By Ozan · #126530 ·
Re: HP 3456A Repair help needed
Ozan, THANK YOU! The 100k resistor had failed open. I can¡¯t believe it. I'm slightly embarrassed, because I was sure I had already checked these. It is always a great idea to have a second set of
By John Quinn · #126529 ·
Re: HP 8640B stiff main tuning
Roy is right. In many greases, one of the major heavy components is soap. Look at what happens when soap residue hardens. But, be careful; not all soaps dissolve in water. Meths can sometimes help. 73
By Brian · #126528 ·
Re: H/P 8753B disassembly
Thankyou Peter - just what the Doctor ordered............................Don C.
By donald collie · #126527 ·
Re: HP 3456A Repair help needed
----- Are resistors R122 and R143 approximately correct and can you trace connectivity from TP104 to gate of Q103? The resistors don't need to be accurate but voltage at gate of Q103 should follow
By Ozan · #126526 ·
HP 3456A Repair help needed
Hello, I'm looking for help repairing my beloved HP3456A DMM. It is a later made model (serial #2201A13361) with most of the IC's date codes from 1984. When I received the unit several years ago, I
By John Quinn · #126525 ·
Re: HP 8640B stiff main tuning
The issue here is the same thing that causes fans to not work well when they age. The original lubricant is made up of a number of different fractions, and over long periods of time the lighter ones
By Roy J. Tellason, Sr. · #126524 ·
Re: H/P 8753B disassembly
Try the manual 08753-90156 [image: image.png] [image: image.png] etc, there are pictures of the assemblies. Be very careful in the HV area as static can blow components (the DAC I believe). Make
By peter bunge · #126523 ·
H/P 8753B disassembly
In damp weather my 8753B EHT plays up causing the display to disappear, and reappear rapidly, as though something is tracking. I have decided to clean the soot off all the EHT components with
By donald collie · #126522 ·
Re: 4395A software
Rico, Excellent work. Wondering if you found out how the calibration constants are stored?
By ROMDUMP · #126521 ·
Re: 4395A software
Hi Sergey, I found a way to upgrade the options to 1D6, 010, 001 This is the reference: How to upgrade: 1. Change this line to this values: 2. Calculate the Checksum over this area: 3. Add +1 =
By Rico Sonderegger · #126520 ·
Re: HP 8640B stiff main tuning
I have just put 8640B Service Manual Volumes 1 and 2 inc CCT Pn 08640-90215 May 1991 .pdf Onto this site in the files also other info including 8640 note for sticking tuning Paul
By Paul Bicknell · #126519 ·
Re: HP 8640B stiff main tuning
Avoid dissassembly. Get service manual. Try some gentle solvent then lube on the shaft , perhaps Iso Alcohol? Jon
By Froggie the Gremlin · #126518 ·
Re: HP 8640B stiff main tuning
No, its been sitting on the bench in operating position. Electrically, the oscillator works fine with no problems, so I don't think its a problem with the internal grease migration. Its just that the
By mondial · #126517 ·