Per the usual online service manual for the 475, the four tunnel diodes are designated CR556, CR566, CR776 and CR786. The first two appear on the A8 Trigger Generator and Sweep Logic circuit board (fi

Unless it’s a different Groups.io <http://groups.io/> forum I’m thinking of, wasn’t editing turned on in the early days of using Groups.io <http://groups.io/>, and didn’t that result in a barrage of e

I’d consider that a feature, not a bug. :-)

Don't overlook the 577 as an alternative. You give up the 576's funky alphanumeric display, graticule illumination, and perhaps a wee bit of test voltage/current range but gain more common CRTs (also

When it stays inside electronic components, they work. When it comes out, they stop working. Magic!

I suppose it could be, but given the instrument was acquired here in the UK (though it’s US-built) I think Chris’s answer may be more likely. It would be nice to find a definitive example of the logo

Thanks! That makes sense and explains why it seems familiar — I must have seen it on other gear, though until now, not any of mine.

I've created an album in photos at https://groups.io/g/TekScopes/album?id=267521 The picture is of my recently-acquired Tek 109 pulse generator. I'm curious about the company (I assume) button sticker

Mentioned earlier in this thread, it’s probably a 6R1 plugin for the 567 oscilloscope. In other words, one of these? https://w140.com/tekwiki/wiki/6R1 In one of these? https://w140.com/tekwiki/wiki/56

Alan A., if you are interested in selling one or more of the 7623A and a 7A13 and a flexible extender, please email me. I'm in the UK.

Turn the intensity down, and the out-of-focus should resolve.

I can imagine all manner of problems trying to run 16 analog audio signals over one cable. But put a good A/D converter at each audio-to-analog transducer -- or as close to it as is feasible -- and yo

I curve trace tubes on my 577 but there's no onboard provision for filament power, so I use my bench supply. The extra banana plug connections are for Kelvin sensing.

I’ve posted image files to the TekScopes Groups.io <http://groups.io/> photo album entitled "Tektronix 577 V/Div and Step Gen knobs.” Unfortunately, the ambient lighting is poor (late afternoon and cl

The variable volts/div controls on my 1A4 and 3A3 are the same. Must have been a feature for a while. It works exactly like the control had a stop, except there's no stop. When you pass the detent the

I thought there was a chance I might have made notes of the repair, and sure enough I did: Q1234 151-0406-00 Transistor:PNP:TO-39 04713 ST1264 2N5401 Q1226 151-0347-00 Transistor:NPN:TO-92 04713 SPS79

My first 577 (a D1) was very dim — and it came with a spare CRT — but essentially worked for a while after I got it home. Then it suddenly went completely dark. Rapid onset blackness seemed unlikely t

Where, and what, is this 75th anniversary consolidated PDF? It wounds interesting, but I’ve never heard of it.

They’re for a Tek 571 curve tracer. In fact, they’re precisely the (optional accessory, I think) adapters I don’t have for my 571. Though my 571 is a repair work in progress that’s on hold whilst I wo

I asked about that. I wrote: "The CRT has clearly been replaced with a smaller than original replacement. Do you know what the replacement CRT is from? Have there been any other replacements and/or mo