Service manual

Wells-Garnder Color Vector Monitor Guide
Page 9 of 73
If you have a P314 deflection board, in addition to the changes listed above, you should upgrade
the following parts:
Differences between P314 and P327 (P339) deflection boards:
• "Input Protection Circuit" added (see additional text later on).
• R106 (22 +/-10%) changed from 2W to 3W.
• Q101 (PNP) changed from Type MPSA56 (TO-92) to NTE50 (TO-202). (*)
• F100, 101 (Slow-Blow) changed from 5A to 6.25A.
(*) The Zanen "Get Well Kit" uses the original specs and does not include these upgrades.
Since the circuits are essentially the same, you can use 5 Amp fuses in P327/339 deflection
boards without any problems. It is safe to say that you can (and more importantly, probably
should) put 6.25 amp slow-blow fuses in your P314 boards at those two locations.
The very first run of P314 deflection boards had design defects in them, which were evidently
identified after the PCBs were produced but before they were populated. If your deflection board
says "85X0147" at the top then it is from the very first batch. Later batches say "85X0147C" (I
have never seen an "A" or "B" suffix). The "C" revision has C605 (0.001uF +/-20%, Type-Z5F
capacitor) in the upper right corner but since the original version of the deflection board does not
have a spot for it, it was soldered piggyback onto R602. Some boards use a 0.005uF capacitor
instead but you should change this to a 0.001uF if you have the soldering iron out anyway. The
original version of the PCB has ZD100 labeled as R104 and ZD101 as R105, respectively, even
though there are always Zener diodes in those spots regardless.
A comparison of the P315 and P329 versions of the HV PCBs and their documentation yields
several conflicting differences, which are summarized below. The values marked with an asterisk
(*) are the ones you should use regardless of which PCB you are working on (with the caveat
that the resistors should be "matched"; do not just change the value of one without changing the
values of all the others. The capacitor changes can be made individually). If you use all of the
asterisk marked values, you will upgrade your P315 to a P329 except that you, obviously, will
not have the over-voltage protection portion of the P329 HV board.
+-------+--------------------------------+-------------------------------+
|Part # | Value in document or on PCB | Document/PCB referenced |
+-------+--------------------------------+-------------------------------+
|*C901 | 100uF @ 50V Alum Electrolytic | P329 HV unit PCB |
| C901 | 100uF @ 35V Alum Electrolytic | P315 HV unit PCB |
| C901 | 100uF @ 50V | TM-183 3rd printing Schematic |
| C901 | 100uF @ 35V | TM-183 2nd printing Schematic |
| C901 | 100uF @ 100V | 19K6400 service man Schematic |
| C901 | 100uF @ 35V Alum Electrolytic | TM-183 3rd printing Figure |
| C901 | 100uF @ 35V Alum Electrolytic | TM-183 2nd printing Figure |
| C901 | 100uF @ 50V Alum Electrolytic | TM-183 3rd printing Parts List|
| C901 | 100uF @ 35V Alum Electrolytic | TM-183 2nd printing Parts List|
| C901 | 100uF @ 100V Alum Electrolytic | 19K6400 service man Parts List|
+-------+--------------------------------+-------------------------------+