Re: 577 D2 question(s)

Paul Amaranth

Early on, Tek listed the 5000 mainfame and display unit seperately, so
you could get a 5103 frame and a D11 storage display. That doesn't
seem to have lasted very long so it gets very confusing, but the only
difference between a D10 or D11 and the 577 display is the probe
callibration terminal on the front.

One of the big advantages of the 577 over the 576 is the ease of replacing
the CRT unit if it goes bad. You should be able to find a donor 5000 scope
around $50. Despite the huge screens nobody wants them because of the low
bandwidth. Heck, you can probably find one free if you want to look hard

I have an old 5000 scope with a D11 storage display that I want to put into
my non-storage 577 one of these days.

Go ahead with the full rejuvination, you can't lose much and you might get
a couple hundred hours out of it. That will give you time while you look
for a 5000 donor.

What's a 5220? I can't find a reference to that.


On Wed, May 05, 2021 at 11:15:27AM -0400, Eric wrote:
Andy tubes are really available for the 577 d2 they can be salvaged from
one of the 5000 series scopes. If I remember correctly the 5220 is the one
you want to find. It is a direct drop in replacement I can confirm the
scope later today of need be.


On Wed, May 5, 2021, 11:05 AM Andy Warner <> wrote:

Thanks all,
I was hoping it would not be the tube, I have been lucky enough to
avoid that on my other Tek gear.
I'll take a pass at the HV board first, but it sounds like I likely have a
poisoned cathode.

Any reason I should not try a full rejuvenation - including applying some
current limited HT between cathode and grid, or is there a reason you
suggested just overdriving the heater, Bob ?

From the serial #, my unit has the 154-0633-10 tube, which appears to be
unobtainium - sigh.

On Tue, May 4, 2021 at 10:33 AM <> wrote:

The symptom is known as "double peaking" and indicates the CRT has
interface, AKA cathode poisoning. The CRT is near the end of its life.
Applying 12 volts for 10 or 15 minutes to the filament (with the
power off, since, in operation, the filament is at -3400 volts), may
a temporary repair. Access to the filament is easy via a two-pin
on the HV/deflection board.

Bob Haas


Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group of Michigan, LLC | Security, Systems & Software
paul@AuroraGrp.Com | Unix/Linux - We don't do windows

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