1. Replace R174 (10k) with a 1 K
2. Replace R187 (10k) with a 1 K
MODULATION: VR14 or cut R249
AM POWER: VR13
SSB POWER: VR12
1. Find the GREEN WIRE located at point
54 and UNSOLDER it.
2. Resolder this GREEN WIRE to POINT 14
(8.7 V) or to TR 41 collector.
3. Find the YELLOW WIRE on the clarifier
control and UNSOLDER it. Insulate the cut end.
¾¾This wire is no longer used.
4. Find D75 (located near POINT 53 and VR15) and lift one end.
5. Find R135 (33k) and lift one end.
6. Double check all work for shorts.
NO EXPLOSION? Then you should be able to track on TX and RX!
There is a RED wire on the solder side of the PCB, it is up at the front of
the pcb when you take the top cover off.
Unsoldered this wire and check the freq. it should be 26.965 to 27.405 MHz with
the band switch in the Hi position, the other switch is on D/A.
Richard (dickie) G.
CONVERT THE SS3900, 28 Mhz VERSION TO NORMAL OPERATION
These radioês are normally supplied by the manufacturer operating on 28 MHz only.
When sold by dealers they have usually had this mod done, but occasionally there is a need for this infomation
There is also a jumper near the centre front of the main board which enables the pull switch band functions.
On a super star 3900 that there are 4 resisters near the front to the right side of the radio that kept the radio from going 25.615 to 28.305 remove the resisters and the frequencies are expanded.10 Meter additional channels
1. Locate pins #12 and #13 on IC7 (MC14008BCP chip).
2. Using a SPST toggle switch, wire as follows:
Center of toggle switch goes to pin #13
The other goes to pin #12
Your channels should work with your band selector on band D. It should be able to go from 28.300 Mhz. to 28.500 Mhz.
(These 2 radios are the same except for the name)
VR1 - AM/FM S METER ADJUST
VR2 - SSB/CW S METER ADJUST
VR3 - SSB SQUELCH RANGE
VR4 - AM SQUELCH RANGE
VR5 - FM DEVIATION ADJUST
VR7 - CARRIER BALANCE ADJUST
VR8 - RF METER ADJUST
VR10 - FINAL BIAS ADJUST
VR11 - DRIVER BIAS ADJUST
VR12 - ALC ADJUST
VR13 - AM POWER ADJUST
VR14 - AMC
VR16 - CW MON ADJUST
VR21 - Tx FREQUENCY ADJUST
TR32 - IS THE AMC LIMITER
"I don't recommend removing TR32 as it disables VR12 ALC, SSB power will
be at full blast.
Instead clip or remove R249. This only disables AMC not ALC.
Tune L40, L43, L44, and L33 for maximum forward swing on wattmeter.
Adjust AM power for no more than 5 watts dead-key - if running a linear amp
set at 3 watts dead-key.
Adjust ALC for no more than 20 - 25 watts PEP on SSB.
For Talkback remove D80."
Superstar 3900 plus gold dual finals.
Same board as Galaxy 2517 & DX48T.
Move jumper to different pins to get 25.615-28.305 Mhz.
That's it.
This mod was sent to me by Crazy Bob, thank you.
+ 10 KHz Jump Switch
1)Get a SPST switch and mount it in the radio.
2)Find IC 6 & 7 by the PLL chip. You will see J68 and J 69
3)Solder a wire from one side of the switch to J68.
4)Solder a wire from the other side of the switch to J69.
5)That's it .Flip the switch to jump up one channel.Open Clarifier
1)Find D75 and R135 and cut one end of them.
2)On the back of the clarifier knob follow the green wire to the PC board. Cut this wire from the PC board.
3)Now Solder this wire to a constant 8VDC source, like the collector of TR41.
4)Take the yellow wire and cut it from the knob. Tape this wire it is not needed.
4)This should make the radio TX/RX on the same frequency.10 Meter Mod
1) Find IC7 near the PLL chip.
2) Get a SPST switch and mount it in the radio.
3) Solder a wire from one side of the switch to Pin #13.
4) Solder a wire from the other side of the switch to Pin #12.
5) That's it .Put the radio on 'Band D' then flip the switch to jump up to 28.300 to 28.500.Tweak and peak
Audio Limiter - Cut R249
AM Power - VR13
SSB Power - VR12
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