Hi Harvey, If you're not considering selling them, have you considered to just make the gerber files available online (let's say github)? A lot of people now regularly buy PCBs from JLCPCB or pcbway.

I've got a 465 and I didn't know there were any tunnel diodes in it. Where should I go looking for it?

Hi Dave, That network provides temperature compensation of bandwidth. A peaking capacitor (a trimmer) already exists across the emitter degeneration to boost bandwidth. The varactor in parallel

That should have been 1 mA. Raymond

CR39 is a constant current diode, @ 5 mA. It needs the headroom to do its thing. 15V wouldn't be enough. Together with RT39, it supplies a temperature-dependent voltage, which is used to achieve

CR39 is a 1mA current regulator, or constant current diode. It is a high impedance device and will not function at (15 - 4.2 = 10.8v). It supplies bias to CR34, a vari-cap that is part of the

Can someone here explain the purpose of the +55v source to this circuit? I'm am trying to see if I can power the vertical assembly on a bench. I have a very dysfunctional vertical assembly, and would

Congratulations Jared. Important quality aspect is lack of noise in the most sensitive DC ranges. Well, being not that good in color distinction I asked my wife for assistance., I'm glad we didn't

Both effects are present in my opinion, shift between alternate sweeps and chop noise. I added a picture "A17 noise" that might convince you. The noise frequency corresponds tp the chop rate (judged

For those with a 2465A (or maybe B) version; I just received a 2465. Very clean and good looking inside; probably heavy usage, though, considering the status of the blower: noisy. Another thing I

OMG, I am a happy panda! I connected the wires as below and it works! Not bad for a $160 gamble on this probe. :) Luckily my coax (The clear-ish wires) weren't broken so I didn't have to worry about

Wow, thanks for that! There's no way I would have got it correct..... I saw your picture at TekWiki and mine matches there, so I'll rewire my Amphenol plug to match yours and see what happens. Many

Bill, My recommendation would be to, after due deliberation, decide if you are going to Repair, Rebuild, or Restore. They are very very different in terms of how long you and your 'scope will be out

Nasty surprise Jared: in my A6302 S/N B76170 all colors are different! With magnifier glass I feel quite sure they are as follows: A red/white B NC C orange/white D black/white E white F

One comment I'll make is you should test the scope with the "weak" tubes before you condemn them...the Tek manuals for all these scopes emphasize that performance in circuit is the only reliable

Thanks John, to obtain a minimum result I had to put on 492 P: LISTEN at 0, TALK at 1 and EOI at 0. In this way on the HP 7470A emulator on the PC I select acquire from tektronix at address 3 and

After reading about the resurrection of a 575 tracer. I thought I'd ask about my 556 scope. I've had it for about 15 years now and use it from time to time. And it has worked fine so far. When I

In my opinion yes, you reverse the polarity of the Hall voltage. The feedback to current to maintain zero flux in the core would reverse and would explode. If it takes not too much force to dismantle

I re-checked the voltage level of the B7 input and you are correct - It's not -0.4V at all, rather it's shifting between -0.66V and -0.7V. I must have mis-read the display when I first looked at it.

In this context it may be noteworthy that one of the most "digital" function blocks in TTL, the 7413 Schmitt Trigger NAND gate, has found use as the active element in X-tal oscillators for simple