7B92, S/N B052568, No Sweep, Help! Since it has been almost a year since my 7B92 arrived in my new-to-me 7904 I’ve decided that it is time to make it work. I’ve re-posted with a new title since

It would be good to know whether the "hook" changes if you change the sweep speeds (both) and what the nature of the changes, if any , are. Stephen Menasian

Jeff, Swapping boards is a good way to determine problems. Swapping ICs would be next to see if any are bad. Removing the trigger light is easy. It snaps in. Pry the black cap of the back. You can

So I got a second 7B92, and this one mostly works (TIME/DIV shafts are bent, trigger lamp does not illuminate, something wrong with ALT horizontal mode when TIME/DIV knob is pushed in, and delayed

I added a photo here: https://groups.io/g/TekScopes/photo/252850/3326143 Thanks, Barry - N4BUQ

That's correct. Only in mixed mode. Thanks, Barry - N4BUQ

It sounds to me like the beam is being "unblanked" a little early and you are seeing part of the retrace. Are you saying that you only see this in mixed mode? Not in regular sweep mode? -- Jeff

I should add that, other than changing the position of the "hook", changing the SLOPE and/or the LEVEL setting has no effect on this. Thanks, Barry - N4BUQ

Quite. Not speaking of the modifications of case and front plate. Repairing a 3014 using parts from a donor-3012 may be feasible but without documentation, which AFAIK is not available, that'll be

If I set one of my 7B53A plugins to mixed sweep mode, the very start of the trace shows a slight hook-shape where the trace moves to the left before starting a full waveform. The remaining waveform,

I can answer that, anyway. Not really feasible, the 2 channel variants are missing the A/D converters, the attenuators, and all the passives around the attenuators.

Ah, But that order was from Mouser, not DigiKey like mine. My switch was just in a bubble-wrap bag in another plastic bag. Colin.

Well i hooked up the eht to the crt and moved the whole lot to one side,heres a few readings i took,on q387 base i get 8.8v,it should be 2.6!,r290 wiper measures as follows,fully cw=3.44,fully ccw

Hi Dave, I think the subject has come up and I _think_ the filter sections for both are the same - or at least with very little changes but I can't really be sure. Send me your address and I'll get

Barry- I haven't looked and compared 465 and 465B board layouts on the prints, but I figure you might have been down the road before of being asked if these are compatible with a 465? If so, how

All plugins have been spoken for. I'll relist anything that falls through. Thanks, and sorry for any confusion I caused by missing posted replies. -- Oz (in DFW, Texas USA) N1OZ

The main boards for the TDS30xx 4 channel units are different from the 2 channel units. I don't think there is any (practical) way to convert a TDS3012 to a TDS3014 without a total main board

Colin, I purchased the parts for this project from Mouser in January of this year. The Grayhill switch we are discussing arrived packed a plastic tube and included the pins, stickers and paper

Has anyone else had this problem with switches from DigiKey, or am I alone? Colin.

You posted that message in a thread with a different name: "TDS3012 and up". That's unnecessarily confusing. Your question was about converting a two-channel TDS3012 to a 4-channel version (TDS3014).