I don't think you are going to harm modern caps with inrush current in most cases (as you seem to indicate as well with your "lore" comment). The transformer will usually help buffer this inrush. Old

If you’ve ever smelled a burned selenium rectifier (stinking up your office or house for days) you would replace all of them before even turning them on. -- Joe Laffey

In my Eico with the 7-inch meter face I installed a little LM317 circuit to the battery source. No worries about battery replacement/leakgae. No change in accuracy or noise to be seen anywhere either.

Sent in a donation PayPal from my other email address. I don’t need credit per se. So no worry. Thanks for all the hard work. -- Joe Laffey

Unless I am trying to make something look pretty, like a piece of tube gear with a mesh cover, I like to write the install date (or at least month/year) of any replacement caps right on the cap. That

I don't remember precisely, but I seem to recall one of the scopes needing you to turn the readout intensity back and forth *twice* to display the readout. I think this had something to do with the in

Also, if you are inclined to build something. Kerry Wong did a nice video on the topic here: https://www.youtube.com/watch?v=Vr6YsT403DM&t=1s

I have one of the: "Constant Current Electronic Load Battery Discharge Capacity Tester 9.99A 60W 30V" loads from Ebay. It only does 30V (and it will not function above that). It works very well within

Thanks. I had checked there. It has some pictures, but no description. Let me know if anyone needs/wants one. Like I said, I saw four here locally.

Anyone know anything about the Metrotek MG701 tm500 plugin? Anyone interested in one? I saw four at a local store.

The tm5006 also has a high power compartment on the far right. The electrical characteristics appear a little different from the tm500 series, however. -- Joe Laffey [Non-text portions of this message

Not sure how high voltage of a probe you need, but Fluke makes some great ones you can get reasonably priced on eBay sometimes. I got their 5KV model for around $28 delivered last year. Safe, reliable

These are a known failure point, and should be replaced immediately when you acquire such a scope. Mine were already burst when I got my 2465.

That is my thread on the EEVBlog ( with a lot of great info from David ). I just followed the calibration procedure listed for the module. It is not perfectly linear, but it is pretty good. -- Joe Laf

I'd love a 7B87, but they seem tough to find. If anyone has one they want to get rid of give me a shout off list. -- Joe Laffey [Non-text portions of this message have been removed]

If anyone has a spare shelf for a Tek Lab Cart Model 3 I would be interested. Please contact me off list. -- 73 Joe Laffey

Ah... well I did put a 1X probe on the 5V rail and Peak detect mode on the 2232 I saw edge peaks of around 75-90mV P-P. For grins and experimentation/learning tried clipping in various sized capacitor

Well, it was a good thing that my schematic no vertical amplifier came today. Because the same timebase works just fine with the second amplifier 7A26 So now I am really confused as to why the signals

At the timebase plugging, measuring the rails on the trigger board I see -15V rail. 0.32miliVAC RMS +15V rail 0.73miliVAC RMS +5V rail 2.07milVAC RMS When the plugin in NOT triggering the ripple on th

Sounds reasonable. I haven't examined the power supply at all yet, though I didn't see any ripple on the power rails of the vertical amplifier. Will measure power supply itself. It may have original c