Tek 465 or 465M?

[BillWojo]

Are the 465 and 465M the same but the 465M is built more rugged? Looking for my first scope and trying to keep it around 100 bucks. Will be used as a field unit for machine tool repair.
Thank you
BillWojo

[TimNJ]

I own a 465m. I'm not too sure if its any more rugged than a 465. It was sold primarily to the military but I'm almost confident it was built to normal Tek standards. The 465m is more of a 455, and not a 465. Both are great scopes. I'd probabaly get the regular old 465, perhaps the 465B if you have the choice. The 465 has a couple more "modern" features, though really not many more.

[David Hess]

The 465M was contemporary with the 465B but the design was different and the features were more like the 465.  It's environmental specifications are practically identical to the 465 and 465B so I agree with TimNJ that it is not any more rugged.

Besides being newer than the 465 and many 465Bs, the 465M uses integrated triggering instead of tunnel diodes which may make it more reliable.

Personally I would prefer the 465B to the 465M because I prefer alternate delayed sweep to mixed delayed sweep.

[Joule Thief]

The 465M also operates without a ventilation fan. The massive heat sink on the back of the scope dissipates most of the internally generated heat. This feature makes the M a very welcome "silent partner" on the test bench.

The main sections of the scope are assembled in modular format. The vertical section, the horizontal section, power supply, etc are all plug ins. This feature may have been marketed to the military as being more field repairable.

[David Hess]

The 465M also operates without a ventilation fan. The massive heat sink on the back of the scope dissipates most of the internally generated heat. This feature makes the M a very welcome "silent partner" on the test bench.

I wondered about that but the Tektronix catalogs were not clear on this.

The main sections of the scope are assembled in modular format. The vertical section, the horizontal section, power supply, etc are all plug ins. This feature may have been marketed to the military as being more field repairable.

The designs were already pretty modular but I could see this being extended for the military.

One thing I would worry about is that at least going by production dates, there are fewer 465Ms than the others so spare parts may not be as common.  On the other hand, they are newer so fewer spares should be needed.

[Joule Thief]

The designs were already pretty modular but I could see this being extended for the military.

This is correct but the M took it a step further. If you look closely at the left and right sides of the M CRT bezel, you will see the front panel is no longer one piece. Close inspection shows how the vertical amp section and the horiz / trigger section are physically separate modules which take their section of the front panel with them when the module is removed.

[Joule Thief]

http://www.dilette.com/main/dilettesales/images/Tek_465M_05.jpg

http://www.dilette.com/main/dilettesales/images/Tek_465M_02.jpg

[BillWojo]

Does the AN/USM 425 (V) 1 mean anything is different about this scope? Will it do the same as a regular 465M scope?
Thank you
Bill

[David Hess]

That is just the part number for purposes of the Federal Supply System.  When the oscilloscope was ordered with option 49, that is how it was marked.

You can find the details in the Tektronix 1981 through 1985 catalogs which is when it was sold.  Good scans of the catalogs are available online for free.

[PaulAm]

For this age of scope it's useful to have a parts scope.  With the 465M, it's pretty easy to swap modules out.  It is not nearly as easy to swap out the horizontal trigger board on a 465, for example.

You can find modules for sale separately, but it's probably cheaper to buy an entire parts scope.  If you don't need a CRT, you could probably find a complete parts scope for less than $50, although it may take a while.  I picked up a broken 465 for $25 off of Craigslist, for example.

This is a 30 year old scope.  It could work fine for years, but entropy eventually wins.  Murphy says it will break when you most need it, so plan accordingly 

[BillWojo]

Well I just won a Tektronix 465M scope off of Ebay for 117 bucks shipped. Should be here by the end of the week. Now I need to pick up some probes and play around with it some. Found a source of manuals on the web. Should be fun learning and I'm sure I'll have questions for you guys.
Thanks for the help so far.

BillWojo