The HP 3561A - still useful in 2022?

Haven't used one of those since about 1988. The two-channel ones are much better. I used to have a 3562A, which I liked a lot, and a 36660 that I didn't like as well because it used one digitizer for both channels, so that it only went up to 50 kHz in two-channel mode.

I now have a 35665A, which I paid $300 for. It has the same problem but has extra functionality. BTW there used to be an outfit called GLK Instruments that would sell you a customized ROM that turned on all the options. (I have one--it was $50 IIRC.)

Cheers

Phil Hobbs

Thanks, I have a USB/PC-based VNA that works well enough for the small amount of RF stuff I do. But for low-frequency analyzers the options seem more limited. The 3577A seems like the most general-purpose tool but a certified refurb runs about 2k and then probably another 2k for the S parameter test set which seems nice to have but I don't know how often I'd use it...I may just keep my eye out for a working 3562 for around 1k that doesn't seem unreasonable for what you get.

My short list for lab upgrade this year is a low-frequency analyzer and a nice bench LCR meter/component analyzer but I tend to get deep in a hole looking at the options, I don't really want to spend even $300 on this kind of Shenzen-special stuff:

But then pretty quickly you're pushing several grand or more for units from BK, etc.

There's also the HP 3563A "Control System Analyzer" which seems like a pretty useful piece for LF gain/phase also. HP stuff from this era is weird it seems like there's a lot of cross-over and you could turn some tools into any other tool just through options and ROM packages...

These were awesome instruments in their time !

I would love to have one just for nastalgic reasons cuz we used to use these in the 80s.

boB

Mainly looking for a tool for profiling e.g. power inductors and audio transformers, plus some control loop analysis. I'm not sure the 3561 is the best tool perhaps, the lack of swept-sine and other signal injection types is kind of a bummer.

The 3562 and 3563 seem like more appropriate tools for that job. There's a spot down the road from me that carries a lot of this stuff surplus and not paying shipping would be great, I'm planning on picking up a

I'll ask if they ever get some of those two in stock, a G seems a fair price for one in as-is working condition.

There was a 3561A on eBay for $200 plus shipping recently but someone grabbed it first. It was functional but throwing a level 1 error code and I looked it up, like "DMA writeback time violation" or somesuch. That doesn't sound necessarily trivial, a bad memory board or IC to hunt down perhaps. Don't really want to fuss with it...

Getting these calibrated to a high standard is pretty cheap, like 50 bucks per unit.