Tektronix 545B Oscilloscope with 2 additional units - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

prumpfy · 22nd Jul 2021, 5:41 am

I have a 546. This particular CRO has the storage tube.
It also has the small triode input valves in the Vertical amp. The 546 has both vertical and horizontal plugins. t also uses 3 tunnel diodes and two of these have failed.
The delaying timebase is superb to use. It has two modes; DELAY and TRIGGER DELAY.
The trigger delay system didn't work so I redesigned the trigger to use a IC. The inherent risetime of the IC affects the visibility of the transient edge, so it sometimes is hard to use.
I do have the manual which is excellent. Parts of it may be helpful.
I believe there is a group on Yahoo which is into Tek stuff (or maybe CRO's in general. I think you should try to get the proper manual though.
Because of the British Commonwealth and tarrifs, my CRO is made in the Channel Islands.

prumpfy

Diabolical Artificer · 23rd Jul 2021, 7:08 am

Yes, a paper copy of the manual would be better than a PDF I have at present. I've also a PDF of the 545A which has clearer waveforms, so take your point. This scope was made in Guernsey too. Not done any work on this yet, back still out so can't lift scope onto the bench.

Andy.

barrymagrec · 23rd Jul 2021, 8:08 am

Quote:

Originally Posted by prumpfy

I have a 546. This particular CRO has the storage tube.
It also has the small triode input valves in the Vertical amp. The 546 has both vertical and horizontal plugins. t also uses 3 tunnel diodes and two of these have failed.
The delaying timebase is superb to use. It has two modes; DELAY and TRIGGER DELAY.
The trigger delay system didn't work so I redesigned the trigger to use a IC. The inherent risetime of the IC affects the visibility of the transient edge, so it sometimes is hard to use.
I do have the manual which is excellent. Parts of it may be helpful.
I believe there is a group on Yahoo which is into Tek stuff (or maybe CRO's in general. I think you should try to get the proper manual though.
Because of the British Commonwealth and tarrifs, my CRO is made in the Channel Islands.
prumpfy

Do you mean a 549? The 546 is a 50Mhz version of the 545B using the same plugins. Not storage

prumpfy · 5th Aug 2021, 2:27 pm

Nah, sorry, it's a 564.
10MHz. It has the 3A6 vertical amp and the 3B3 timebase.
It was new in about 1962 or so.
Didnt get used much until I first saw it in about 1974.
I finally won it in about 1990, as it was bypassed in favour of a 465? (50MHz portable).
After some years in my shed it developed jumpiness at startup.
Examination of the CRT socket showed there was some corrosion due to corona discharge. I cleaned the tube pins etc as best I could, and for many hyears the CRO was good.
Recently I have put the CRO into use again, and have found there is a lot of TLC needed. The corona corrosion has returned and ATM I am cleaning the pins of the tube and the contacts in the socket show intense blackening. I guess the contacts are a steel material. A few of the tube pins have corroded copper and plating is gone. There are about 4 or 5 pins which are in a bad way. These are the pins connected to the -3500 Volt supply.
The last time I worked on it in the 1990's, the series regulator 6080, was gassy.
I replaced the series regulators with MOSFET, and have replaced a number of the tubes with MOS. Funnily enough, I was rummaging through a box and found a 6080. That's the problem with keeping stuff; oftentimes one forgets to look in all the boxes!

I do have the complete set of manuals for it. Couldnt do anything without them.

22nd Jul 2021, 5:41 am	#21
prumpfy Diode Join Date: Jul 2021 Location: Melbourne, Victoria, Australia. Posts: 7	Re: Tektronix 545B Oscilloscope with 2 additional units I have a 546. This particular CRO has the storage tube. It also has the small triode input valves in the Vertical amp. The 546 has both vertical and horizontal plugins. t also uses 3 tunnel diodes and two of these have failed. The delaying timebase is superb to use. It has two modes; DELAY and TRIGGER DELAY. The trigger delay system didn't work so I redesigned the trigger to use a IC. The inherent risetime of the IC affects the visibility of the transient edge, so it sometimes is hard to use. I do have the manual which is excellent. Parts of it may be helpful. I believe there is a group on Yahoo which is into Tek stuff (or maybe CRO's in general. I think you should try to get the proper manual though. Because of the British Commonwealth and tarrifs, my CRO is made in the Channel Islands. prumpfy

23rd Jul 2021, 7:08 am	#22
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,667	Re: Tektronix 545B Oscilloscope with 2 additional units Yes, a paper copy of the manual would be better than a PDF I have at present. I've also a PDF of the 545A which has clearer waveforms, so take your point. This scope was made in Guernsey too. Not done any work on this yet, back still out so can't lift scope onto the bench. Andy. __________________ Curiosity hasn't killed this cat...so far.

5th Aug 2021, 2:27 pm	#24
prumpfy Diode Join Date: Jul 2021 Location: Melbourne, Victoria, Australia. Posts: 7	Re: Tektronix 545B Oscilloscope with 2 additional units Nah, sorry, it's a 564. 10MHz. It has the 3A6 vertical amp and the 3B3 timebase. It was new in about 1962 or so. Didnt get used much until I first saw it in about 1974. I finally won it in about 1990, as it was bypassed in favour of a 465? (50MHz portable). After some years in my shed it developed jumpiness at startup. Examination of the CRT socket showed there was some corrosion due to corona discharge. I cleaned the tube pins etc as best I could, and for many hyears the CRO was good. Recently I have put the CRO into use again, and have found there is a lot of TLC needed. The corona corrosion has returned and ATM I am cleaning the pins of the tube and the contacts in the socket show intense blackening. I guess the contacts are a steel material. A few of the tube pins have corroded copper and plating is gone. There are about 4 or 5 pins which are in a bad way. These are the pins connected to the -3500 Volt supply. The last time I worked on it in the 1990's, the series regulator 6080, was gassy. I replaced the series regulators with MOSFET, and have replaced a number of the tubes with MOS. Funnily enough, I was rummaging through a box and found a 6080. That's the problem with keeping stuff; oftentimes one forgets to look in all the boxes! I do have the complete set of manuals for it. Couldnt do anything without them.