The 1 MHz oscillators in such hoary old gear as the HP5245 counter and the HP5110A synthesiser driver are identical, consisting of a reference quartz...
Not the same unit, but have a look at this for pointers: http://www.realhamradio.com/GPS-oven-journey.htm ... and the HP5110A synthesiser driver are identical,...
I wish to buy an A25 Reference Board (p/n 3456-25c or equivalent) for an HP 3456A digital voltmeter. I also need a MC68A00P CPU chip (U15 on the A4 board, or...
I wish to purchase two circuit boards for the inside of the probes of an HP 8405A Vector Voltmeter. Ones with blown diodes would be OK as long as the circuit...
Is this unit about 2 RU high and half rack wide? Does it have lots of switches on the front panel? I believe this is an HPIB Bus Exerciser that was used in...
I have a question to do with my beloved 141T Spec/An. With 0dBm input, and the "Log Reference" knob set to 0dBm beside the light that is lit [the lamp that is...
I have one of these beautiful little jems that works perfectly (an HP 6215A), but someone before me dropped it and the plastic rectangular collar that holds...
I get a similar low reading. I think if you go through your Performance Tests in the manual you will find you cannot set the Amplitude Calibration for -30 dbm...
I seem to recall that there is a problem with the 141T system and the sheet aluminum that holds the D style RF connectors that go between the frame and the...
Right; those are the connectors I'm talking about. Nasty piece of mechanical-design work, but to be fair, it has worked for a lot of users for a long time. --...
... I guess the sad part is virtually every supply or other instrument housed in these "impact resistant" cases is broken. The plastic failed, and shrunk, and...
I have a PDF for the manuals but they only have schematics for the power supply. I would like to get complete schematics but particularly looking for the the...
You know that secret government warehouse at the end of "Raiders of the Lost Ark"? East wing, aisle 12, fourth shelf. Right next to Nikola Tesla's death ray...
Thanks for your responses, all. Everybody seems to agree that this is a fault, and not a normal condition, to do with the Amphenol "D" connectors that...
Don, It is definitely not normal for the 8555A, 8552B combo. I just checked my 141T SA system and it is right on spec. 0dB is on the 0dB graticule. That with...
Can anybody comment on whether or not there is an error in the in the faultfinding flowchart on page 8-12 of the 8555A manual. So far there`s three 141T`s that...
Hi Don, maybe this is a helpful link for you: http://www.qsl.net/g8bke/141T_mixer.pdf Regards B. Johann, Cologne ... Date: Tue, 03 Apr 2007 11:08:15 +0200 ...
I just checked my 8554B and it works the way it should so this seems to rule out my IF section and the mainframe. I am using an 8252A (not the B version) but I...
I have the 8753A/B (not C) manual which includes all schematics except the power supply. I think I still have a faded copy of that schematic as well though. ...
That brings to mind a question that was alluded to in a earlier post: What is the result of a burned out 141T SA mixer diode? Burned out mixer diodes are the...
Hi Peter I actually had a bent pin in one of the Ds in one of my units which stopped the plug and socket mating properly, but that was a 110MHz RF head (8553)...
... From memory, the 'mixer' in a 8555A comprises a diode transistor pair and if the diode alone fails s/c then the gain drops somewhat (~20dB is possible)...
... I have been informed (off list) that the mixer is a single diode mixer with a transistor IF gain stage following it. A mixer failure of any sort, in this...
Hi Don & everyone else, my problem may actually be different from yours - please check and respond. When I vary the input attenuator the peak (from the 8552A...
