Re: Tek 453 - Q913 Part Number


Howard Matthews
 

Checking the NTE cross reference, both the 2N3251 and the 2N4122 are
PNP, and are crossed to NTE 159.

Combine that with the fact that although the parts list for Q913
listed the two different transistors for different serial number
ranges, the schematic showed no substantial changes at the same SN
break point, I've come to this tentative conclusion:

Tek got tired of selecting 2N3251s, and found that 2N4122s did the
job better. So, I believe the 2N4122 would be the prefered
replacement for any Tek 453 Q913, SN 100 to 19,999 (and also SN >
20K) - unless you have an early model that you *absolutely must*
restore to *factory mint* condition.

I'm new at this repair game, so if my detective work is wrong, I
would like to be corrected. :]

-Howard

--- In TekScopes@yahoogroups.com, "Rolynn PRECHTL K7DFW"
<k7dfw@c...> wrote:



Q913 - Tek pn 151-0220-00 Silicon 2N4122 for Type 453
oscilloscope
===========================

Now I'm confused.

My manual, with SN 4395 written in, shows 913 as a 0133-00 which
is a
selected 2N3251 (a PNP) and the schematic shows it as a PNP.

That 2N4122 is a NPN.

K7DFW

..._._

Join TekScopes@groups.io to automatically receive all group messages.