Tek 2465BCT question: CRT life?

[NHnewbie]

I recently acquired a Tek 2465BCT (sn B063xxx) from an eBay seller who had done an extensive refurb of this unit prior to selling, including recapping, new NVRAM with recent cal data, new fan, etc. Came with nice options (09/10/1E), four P6137 probes, front cover, lots of accessories, comprehensive operator and service manuals. Cosmetics could pass for new and all checks pass. One minor surprise: the hour "meter" shows about 7100 hours.   What should I expect (in hours) for the life of the CRT?

BTW: The seller is highly experienced with 2465 repair and recommends against installing a heat sink on the U800 IC.

[tkamiya]

Probably no less than two dozen scopes of 70s and 80s vintage went through my lab during last and this year.  I have yet to see one which CRT is just worn out tired.  If it's nice and bright and sharp in focus, and you paid reasonable price for it, I wouldn't worry about it.  Do you see any burn in on your CRT?  That's usually a pretty good indicator of neglect.

[David Hess]

I also have yet to find a Tektronix oscilloscope of that age or older with a confirmed worn out CRT except for early 2213/2215s which operated the CRT heater at too high a voltage.

The 2465 series oscilloscopes I have used however had a "softer" display than their slower contemporaries and this shows up in videos and photographs as well.  I suspect this was a result of their CRT design which relies on greater scan expansion for higher bandwidth with a shorter CRT at lower deflection voltages.

BTW: The seller is highly experienced with 2465 repair and recommends against installing a heat sink on the U800 IC.

That is my recommendation also.  I think the problem with U800 was improper mounting which caused excessive stress on the lead frame and die attachment.

[NHnewbie]

Thanks to those who responded. The CRT will likely outlast me!

Rick
K8EZB

[0culus]

I also have yet to find a Tektronix oscilloscope of that age or older with a confirmed worn out CRT except for early 2213/2215s which operated the CRT heater at too high a voltage.

The 2465 series oscilloscopes I have used however had a "softer" display than their slower contemporaries and this shows up in videos and photographs as well.  I suspect this was a result of their CRT design which relies on greater scan expansion for higher bandwidth with a shorter CRT at lower deflection voltages.

*snip*

I've found that if you're working under 20 MHz, the bandwidth limit feature massively sharpens the traces.

OP, I recently got my 2465B refurbished from a reputable seller on ebay and it's CRT looks to be in great shape. You'll have to let me know how you like the options. I was thinking of perhaps being on the lookout for a second one with a few options (mine is a bare bones 2465B).

[NHnewbie]

OP, I recently got my 2465B refurbished from a reputable seller on ebay and it's CRT looks to be in great shape. You'll have to let me know how you like the options.

Only a little time with this scope so far but here are initial impressions re options:

Option 09 (CTT and WMR)/ Option 1E (CTT with EFR):Counter/Timer/Trigger, Word Recognizer and External Frequency Reference: Overall, this seems quite useful; the external freq ref (Option 1E) probably not relevant for most users, but does add another digit of resolution (8 vs 7 digits) to freq measurements.

Options 10 (GPIB); havent tried this and suspect useful to a small minority of users.

My scope does not have Option 05/5H (TV & HDTV), or Option 01 (DMM). I suspect the TV options will not be relevant to most present day users. As for the DMM, may be useful if scope is used mostly as a portable, but for bench use, a separate DMM would be my preference.

RB

[tkamiya]

If anyone needs spare parts, do let me know!  I have Tek2465BCT where counter module is defective.  I don't mind parting it out.

[0culus]

OP, I recently got my 2465B refurbished from a reputable seller on ebay and it's CRT looks to be in great shape. You'll have to let me know how you like the options.

Only a little time with this scope so far but here are initial impressions re options:

Option 09 (CTT and WMR)/ Option 1E (CTT with EFR):Counter/Timer/Trigger, Word Recognizer and External Frequency Reference: Overall, this seems quite useful; the external freq ref (Option 1E) probably not relevant for most users, but does add another digit of resolution (8 vs 7 digits) to freq measurements.

Options 10 (GPIB); havent tried this and suspect useful to a small minority of users.

My scope does not have Option 05/5H (TV & HDTV), or Option 01 (DMM). I suspect the TV options will not be relevant to most present day users. As for the DMM, may be useful if scope is used mostly as a portable, but for bench use, a separate DMM would be my preference.

RB

Yeah I doubt I'd need the DMM or the TV stuff, but the CTT option seems like it could be nice to have. I think mine actually does have the external frequency reference, now that I think about it. Thanks!

If anyone needs spare parts, do let me know!  I have Tek2465BCT where counter module is defective.  I don't mind parting it out.

Will definitely keep that in mind!

[NHnewbie]

If anyone needs spare parts, do let me know!  I have Tek2465BCT

Possible interest in some of the boards if a late instrument serial no. (B050000 and higher) and boards are working.

RB

[David Hess]

The 2465 series oscilloscopes I have used however had a "softer" display than their slower contemporaries and this shows up in videos and photographs as well.  I suspect this was a result of their CRT design which relies on greater scan expansion for higher bandwidth with a shorter CRT at lower deflection voltages.

I've found that if you're working under 20 MHz, the bandwidth limit feature massively sharpens the traces.

This is *with* the 20MHz bandwidth limit engaged and I hardly see any difference in noise with or without the 20MHz bandwidth limit on my 150MHz 2445B.

OP, I recently got my 2465B refurbished from a reputable seller on ebay and it's CRT looks to be in great shape. You'll have to let me know how you like the options. I was thinking of perhaps being on the lookout for a second one with a few options (mine is a bare bones 2465B).

My 2445B has video triggering but that is hardly useful these days.

I think the counter/timer option would be the most useful but I have not used it myself.  The contemporary 2247A has more useful automatic measurement capability since it operates continuously.

[med6753]

The 2465 series oscilloscopes I have used however had a "softer" display than their slower contemporaries and this shows up in videos and photographs as well.  I suspect this was a result of their CRT design which relies on greater scan expansion for higher bandwidth with a shorter CRT at lower deflection voltages.

I've found that if you're working under 20 MHz, the bandwidth limit feature massively sharpens the traces.

This is *with* the 20MHz bandwidth limit engaged and I hardly see any difference in noise with or without the 20MHz bandwidth limit on my 150MHz 2445B.

There is a noticeable difference in trace noise on the 2465's because of the much higher bandwidth.

My 2445B has video triggering but that is hardly useful these days.

I think the counter/timer option would be the most useful but I have not used it myself. 

It is very useful.