[R-390] hp 410B VTVM ( for working on my R-390A)

[Barry]

>Sam,
>
>I would not want to change to a SS diode, as tempting as that might be. 
>  A 1N66, etc. would be OK but you would loose a lot.  Diodes are 
>limited to about 20 vac and 250 MHZ but the 2-O1C can handle over 300 
>volts, depending on frequency.  The upper frequency limit is over 700 
>MHZ.  Hard to duplicate that with a SS diode, unless a 20 volt limit is 
>OK for your app. The 410-B should use the 2-O1c not the EA-53, unless it 
>has been modified. BTW, I have 2-O1C, NIB.  Trade?
>
>73,
>
>Bill, K3PGB

I don't think that's correct.  HP built the 410B for both diodes in different probe configurations.

Barry - N4BUQ