[Amps] Advice on instruments for ham use

[Bill L. Fuqua]

I have not read all the emails about this subject but I do have some experience to relate to the list. 

1.   455 and 465 scopes are fine except when the attenuator switches wear out. They consist of cams pressing small gold plated fingers onto small gold plated pads on the little circuit boards. Once the gold is worn off the switches corrode and they are no good. 

2. For repairability  the 453 and 454 scopes are better. They have smaller screens but the resolution is about the same due to the fact that the 455 and 465 scopes use post acceleration potential that creates a larger spot due to the space charge causing the electrons to spread when they are traveling slowly before the post acceleration potential 

3. If you don't need a portable scope I prefer the 7000 series. They are very modular and if one item fails. Main frame,  vertical or horizontal plugins are easily replaced at low cost. S lot of these hit the surplus market when IBM closed down a lot of older factories and emptied out lots of warehouses.  The military has dumped a lot of these after Desert Storm when they decided to empty loads of warehouses as well.  Also you can get lots of other plug-in modules as well such as frequency counters, spectrum analyzers, digital voltmeters etc.  I have  several 7904 and 7704 scopes. And they have been just fine. 


All of our 465 scopes have been surplused at work after the attenuator switches have worn out.  

73
Bill wa4lav
same due to the fact that the 455 and 465 scopes use post acceleration potential that creates a larger spot due to the space charge causing the electrons to spread when they are traveling slowly before the post acceleration potential 

3. If you don't need a portable scope I prefer the 7000 series. They are very modular and if one item fails. Main frame,  vertical or horizontal plugins are easily replaced at low cost. S lot of these hit the surplus market when IBM closed down a lot of older factories