Favorite unsung TE heroes - Page 1
Forum section: electronics / testgear

author: HalFoster
author_rank: Frequent Contributor
timestamp: June 11, 2019, 03:38:58 pm
content: All-Was using my HP 3336C last night and it occurred to me that it's not very well known or used despite it's capabilities. It's big brother the 3335A is much the same although, in my opinion, somewhat better know. It seems as though a lot of people now seem to think that anything that doesn't operate in the GHz can't really be taken seriously. Note: Not the members of this forum generally, but other less enlightened folksIn my experience, there is a lot that can be done below 21 or 80 MHz - and especially with the accuracy of the attenuators in either one - vary little today can compare and what does will set you back as much as some houses. Yet either of them can be had, working, for under $250 USD just about at any time. They are not near as expensive to run through a cal lab (if they even need it) as modern equipment.So, what are other bits of TE are undeservedly not well know? Of course, IMHO, any of the Power Designs Precision Power Sources are very, very high on the list.Hal

author: oPossum
author_rank: Super Contributor
timestamp: June 11, 2019, 03:48:23 pm
content: HP 545A Logic Probe.

author: tggzzz
author_rank: Super Contributor
timestamp: June 11, 2019, 04:49:43 pm
content: Quote from: HalFoster on June 11, 2019, 03:38:58 pmIMHO too. My 2020 is a delight to use.

author: HalFoster
author_rank: Frequent Contributor
timestamp: June 11, 2019, 06:11:58 pm
content: oPossum: Wow. That really is nice - and I didn't have a clue it existed. 5ns pulse - sweet.tggzzz: I'm kinda addicted to them (TEA is made for me) as I have 13 various ones so far... although C500s are probably my favorites.Hal

author: tggzzz
author_rank: Super Contributor
timestamp: June 11, 2019, 06:15:10 pm
content: Quote from: HalFoster on June 11, 2019, 06:11:58 pmMy fetish is for Tek 1502s.

author: oPossum
author_rank: Super Contributor
timestamp: June 11, 2019, 06:35:53 pm
content: The attention to detail in the design of the 545A/546A/547A is amazing. Most of an issue of the HP Journal was dedicated to these instruments.https://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1976-12.pdf

author: chris_leyson
author_rank: Super Contributor
timestamp: June 11, 2019, 06:38:46 pm
content: CV2171 noise diode makes a nice 20dB excess noise souce, useful up to a few hundred MHz with careful layout.

author: bd139
author_rank: Super Contributor
timestamp: June 11, 2019, 06:46:50 pm
content: HP 400E. Bought it for no purpose. Use it all the time. Now after matching 427A for vanity reasons

author: exe
author_rank: Unknown
timestamp: June 11, 2019, 09:11:58 pm
content: Quote from: bd139 on June 11, 2019, 06:46:50 pmWhat do you do with it??

author: bd139
author_rank: Super Contributor
timestamp: June 11, 2019, 09:45:38 pm
content: As the thing has a quite ridiculously large chunk of flat bandwidth it usually has a dummy load strapped to it and gets used as a power meter for low HF stuff. Also audio power measurements. small signal amplifier gain measurements. Peaking filters. AC-DC conversion (I used it in an ALC loop a week or so ago to test something). It's just nice to have on the bench as well.

author: nctnico
author_rank: Super Contributor
timestamp: June 11, 2019, 09:52:33 pm
content: I liked the HP3314A function generator I used to own. A bit loud though... Another nice instrument I have is a dual channel Kikusui analog AC voltmeter. Very handy when dealing with audio circuits which need to have specific output levels. Having the input and output level measured at the same time make life easy.

author: syau
author_rank: Frequent Contributor
timestamp: June 11, 2019, 11:15:30 pm
content: Quote from: tggzzz on June 11, 2019, 06:15:10 pm1502 is well known in the aviation industry in the 80’s which used to locate short / open coaxial cable along the long run of the aircraft.PS. I still looking for a functional unit without blowed up tunnel diode

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: June 11, 2019, 11:34:49 pm
content: Quote from: syau on June 11, 2019, 11:15:30 pmHere they propose a Russian substitutehttp://w140.com/tekwiki/wiki/1502

author: tggzzz
author_rank: Super Contributor
timestamp: June 11, 2019, 11:44:53 pm
content: Quote from: syau on June 11, 2019, 11:15:30 pmThe 1502 was particularly associated with patriot missile batteries. I believe the 1502b was mandated for some aerospace tests, and there is now a modern equivalent.I've had four 1502s; all tunnel diodes were intact, unlike their power supplies.

author: syau
author_rank: Frequent Contributor
timestamp: June 12, 2019, 01:39:51 am
content: Quote from: tggzzz on June 11, 2019, 11:44:53 pmI missed the day with 1502, trying to locate a shorted coaxial in a de-powered aircraftThe screen of the 1502B/C is too bright in this situation and I hate those pixel on the LCD screen.

author: edavid
author_rank: Super Contributor
timestamp: June 12, 2019, 01:56:52 am
content: Clarostat 240-C power decade resistor.

author: kj7e
author_rank: Frequent Contributor
timestamp: June 12, 2019, 02:02:53 am
content: HP 53310a, makes a heck of a frequency counter. Also found the HP 3400a, the RMS version of bd139's 400e, is a very useful instrument for a quick AC RMS measurement of signals.

author: D Straney
author_rank: Frequent Contributor
timestamp: June 12, 2019, 03:44:52 am
content: Probably not quite the kind of thing you're looking for, but after using one for a while at work I'm surprised the Newton's 4th "Frequency Response Analyzers" aren't more popular:https://www.newtons4th.com/products/frequency-response-analyzers/psm3750/If you don't need Ghz-level stuff they're way cheaper than the comparable bigger-name network analyzers we looked at, and even more importantly the inputs and outputs are isolated (with something like 20-35 pF common-mode I think) - so besides the normal filter response testing, etc. where everything's ground-referenced, you can also stick the output directly in series with a control loop and measure its transfer function without bothering with injection transformers and all kinds of other shit. Complete joy for checking power supply stability. Interface is definitely quirky and the PC software is pretty bad (for when you want to save plots) but it's worth it so far.