Subject: TS930 repair notes (long)
From: [email-masked] (robert.f.casey)
Date: Wed, 18 Dec 1991 18:24:24 GMT

the following is a series of packet articles on the TS930

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To
  379 BF    914   0 15-Dec 1708 KD2EJ  29228_WB2QJA INFO@ALLBBS ()
 Sb: TS-930S CW PITCH TONE

PERMISSION GRANTED FOR RELAYING AS INDICATED ON KENWOOD BBS.

SB-872

TS-930S CW Pitch Tone Shift                            7-06-83

Some users of the TS-930S have reported a slight change in the CW pitch
tone when the MONI switch is turned ON and OFF.

This may be corrected by changing the following components:

On the Signal unit (X57-1000-XX) change R826 from a 1 K ohm resistor to a
10 K ohm resistor and remove C601, a .022uF capacitor from the foil side of
the circuit board.

Notes:  This change is applicable to units before serial number 3070221
only.
Time required for this change is 1/2 hour.
CLM
(c) 121589TKC

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To
  382 BF    828   0 15-Dec 1717 KD2EJ  29231_WB2QJA INFO@ALLBBS ()
 Sb: TS-930 15M INTERNAL BEAT TONE.

PERMISSION GRANTED FOR RELAYING AS INDICATED ON KENWOOD BBS.

SB-884

TS-930S 15 Meter Internal Beat Tone                            1-27-84

Some users have reported an internal beat tone that appears every 10 KHz ,
when operating in the range of 20.000 to 21.500 MHz.  Apparently the RV
terminal of Switch Unit H is being affected by the 1st loop of the PLL
unit.  The cure is relatively simple.  Add a .01uF 50v Disk ceramic
capacitor from the RV terminal to ground.
CLM

Time required for this modification is 1/2 hour or less.
(c) 121589TKC

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To
  383 BF   2392   0 15-Dec 1720 KD2EJ  29232_WB2QJA INFO@ALLBBS ()
 Sb: TS-930S INTERMITTENT TX PWR OUT.

PERMISSION GRANTED FOR RELAYING AS INDICATED ON KENWOOD BBS.

SB-886

TS-930S Intermittent TX Power Output                            5-11-84

The following procedure should correct any tendency of the TS-930S to
exhibit intermittent TX power output.  Most of the reported cases of thsi
nature have been traced to poor contact of one or more plated thru holes
mentioned below.  Careful adherence to this procedure should prevent
reoccurrance of this symptom.

Procdeure:

1.   Remove the top and bottom covers.
2.   Remove the 10 screws  securing the final unit to the chassis.
3.   Disconnect all cable assemblies from the final assembly, and remove it
from the radio.  The fan motor cable may have to be removed for easy
access.
4.   Remove all Final Unit PC board screws and turn the circuit board foil
side up.
5.   Desolder Q6, D2, and the plated-thru hole connecting the foils from
R20 and Q8 base together (between T2 and VR1).  Do not remove the
components!
6.   Carefully remove the green solder resistant coating from the immediate
areas of these six points, so that there is bare copper foill up to and
surrounding the eyelets.
7.   Carefully resolder these six points, and those listed below:
     Q1 Emitter and base
     D4 anode and cathode
     Q2 Emitter and base
     Q3 Emitter and Base
     Q7 Emitter and Base
     Q4 and Q5 Base and collectors
Plated-thru hole between C36 and C15
     (2) Plated-thru hole sby the molex connector.
     Check and resolder the input and output coax connectors.
8.   Double check your work to ensure that there are no solder bridges or
splashes.
9.   Check the value of R19.  If it is not 6.8 K ohms, change it so it is.
10.  Reinstall the final assembly, and readjust the idle bias currents of
the driver and final transistors in accordance with Service Bulletin 867.

CAUTION:  ENSURE THAT NO CABLES ARE PINCHED BETWEEN THE FINAL ASSEMBLY AND
CHASSIS WHEN REINSTALLING THE FINAL UNIT.  THE FAN CABLE IS ESPECIALLY
VULNERABLE, SO PAY CLOSE ATTENTION!

Time required for this modification is 1 hour or less.
(c) 121589TKC

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To
  378 BF   1294   0 15-Dec 1706 KD2EJ  29227_WB2QJA INFO@ALLBBS ()
 Sb: TS-930S PLL UNLOCK

 PERMISSION GRANTED FOR RELAYING AS INDICATED ON KENWOOD BBS.

SB-869

TS-930S PLL Unlock                                  3-29-83

Some users of the TS-930S have reported a problem where the PLL will
sometimes not lock (digital display does not come on) if the power switch
is turned off and on while xx.499.9 MHz is displayed, after the unit has
warmed up.  This may occur also in the FSK mode.

This may be caused by detuning of VCO-2 and VCO3 in the PLL unit (X50-1880-
00).  This may be cured by a simple increase in the voltage obtained in the
PLL alignment procedure.  Make the following change in your service manual.

Service Manual page 58.

3. VCO-3  T14 change 3.7v to read 4.2 vdc
4. VCO-2  T15 change 3.0v to read 3.5 vdc

Notes:    1. Be sure to adjust T14 and T15 of VCO-2 and VCO3 whenever a PLL
related circuit is serviced.
          2.   This change applies to units before S/N 306XXXX.
          3.   Installation time for this change is 1/2 hour or less.

JEB/sh
(c) 121589TKC

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To
  380 BF    901   0 15-Dec 1710 KD2EJ  29229_WB2QJA INFO@ALLBBS ()
 Sb: TS-930S RF FEEDBACK

PERMISSION GRANTED FOR RELAYING AS INDICATED ON KENWOOD BBS.

SB-874

TS-930S RF Feedback                            7-15-83

For reports of  RF feedback from the external speaker, especially when
using a vertical antenna, or a linear amplifier, check for correct
installation of capacitor C16 on the EXT SPKR jack.

C16 should go from ground to the white wire on the opposite side of the
jack.  Some units have the capacitor soldered to the middle terminal in
error!

Note:  This bulletin is applicable to radios with serial numbers prior to
3070420.

Time required for this change is 1/2 hour.
CLM
(c) 121589TKC

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To
  377 BF    840   0 15-Dec 1703 KD2EJ  29226_WB2QJA INFO@ALLBBS ()
 Sb: TS-930S SSB TX TONE QUALITY

PERMISSION GRANTED FOR RELAYING AS INDICATED ON KENWOOD BBS.

SB-867

TS-930S SSB TX Tone Quality                                  3-2983

The transmitted audio tonal quality of the TS-930S may be improved by the
following procedure:

In the TS-930S Service Manual page 64, make the following change:

5. 100 W Final Bias VR2 adjust for 70 ma
                    VR1 adjust for 1.3A

Note:  This change is applicable to units with serial numbers prior to S/N
3080001.

Installation time for the procedure is 1/2 hour or less.

JEB/sh
(c) 121589TKC

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To
  381 BF   1385   0 15-Dec 1713 KD2EJ  29230_WB2QJA INFO@ALLBBS ()
 Sb: TS-930S SERVICE NOTES ON AT.

PERMISSION GRANTED FOR RELAYING AS INDICATED ON KENWOOD BBS.

SB-877

TS-930S Service Notes on AT-930                            8-23-83

Some of the symptoms and cures for troubles that have been encountered with
the AT-930 are listed below.

1.   The motors do not stop on all bands.
     
     Possible causes:
     a.   Cold solder joint of platee VCJ wire.
     b.   Cold solder joint of L18 lead.
     c.   Cold solder joint of the wire between pin 13 of Q39 and R139, D33
and R138.

2.   The motors do not stop on the 7 MHz band.

     Possible Cause:     
     The rotor of VC2 contacts (shorts against) the stator.

3.   The motors do not stop on the 28 MHz band.

     Possible Cause:
     Cold solder joint between D33 and R84

4.   The AUTO mode does not reset.

     Possible Cause:
     The wire from R138, R139 and D33 may touch Q39 pin 14.

5.   The motor stop when SWR is at Maximum.

     Possible Cause:
     The wire from R138, R139 and D33 touches Q39 pin 14 and the foil is
broken around VC1.

Time required for this change is 1/2 hour.
CLM
(c) 121589TKC
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Note: I haven't tried or verified this, proceed at your own risk.  WA2ISE