585A/RM585A Mod Info
Contributed by Stan Griffiths
If your Tek 585A or RM585A has the following serial no., you may be
interested in the following mod info:
585A: Prior to S/N 9250
Heerenveen-Built 585A: Prior to S/N 700400
RM585A: Prior to S/N 1020
To protect your vertical output tubes, (V1274 and V1284) your regulator,
(V737B) and your relay, (K601-4) the contact location of the relay is changed
from the junction of C700 and the plate of V677B and 737A to the junction
of D702A and B and D672 A and C.
- Locate the gray-red-brown wire on terminal 2 of K601. See Fig.1.
- Remove the two gray-red-brown wires from CSJ-11 on the sweep chassis.
One of these two wires is the other end of the wire referred
to in step 1.
Using an ohmmeter, determine which wire connects to K 601-2. Unsolder it
from the relay (terminal 2) and cut it off on both ends close to the cable,
as it will not be reused.
Resolder the other gray-red-brown wire back to CSJ-11 (+325 unreg)
- Remove the bare wire that connects CSA-8 to CSA-12 on the rectifier
bracket. See Fig. 3.
- Using the same technique as in step 2, locate the gray-red-red wire
that connects K601-1 to CSA-9 on the rectifier bracket and solder the ceramic
strip end of this wire to CSA-8.
Resolder the other gray-red-red wire back to CSA-9.
- Install a gray-red-brown wire from CSA-12 on the rectifier bracket
to terminal 2 of K601.
- Install a bare wire from CSD-7 to CSD-8 on the power chassis. See fig.
- IMPORTANT: Check the relay for welded contacts. Separate them and burnish.
- This completes installation. Update the circuit diagram in your manual
according to fig.5.
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