Uniden-/President
WASHINGTON
(858 PLL)
MODULATION
VR7 or cut D23
AM POWER: VR8
SSB POWER: CT7
RX COILS: L3 thru
L8
TX COILS: L32,L30
SAMS
PHOTOS: #126,127,128,170,171,176,179,200,207
POWER TWEAKS
(Mike circuit changes:)
1. UNSOLDER
banded end of diode D21 and lift up.
2. UNSOLDER banded
end of diode D22 and lift up.
3. SOLDER a 4.7 k
resistor across where D21 and D22 was unsoldered.
4.
Replace R78 (27k) with a 56k.
5. Replace R84 (4.7k)
with a 2.2k.
(Transmit circuit changes:)
1. Replace
C174 (56pF NPO) with a 82pF NPO ceramic capacitor.
2.
Replace C173 (180pF NPO) with a 220pF NPO ceramic capacitor.
3. Re-tune coils L32,L30,L29,L28 and VR8 for maximum forward AM
power.
CLARIFIER
1. UNSOLDER and remove D30.
2.
UNSOLDER and remove D29.
3. Add a jumper in the holes
from where you removed D29.
4. Cut the end of R119 that
is closest to D29.
5. Add a jumper wire from R119 (the
cut end) to the banded end of D44.
6. Follow the
PURPLE/WHITE
wire form the clarifier control to the PC board and UNSOLDER IT.
7. Resolder this wire to the PC board ground.
8. If all went well, you should slide 1 kc up and 3 kc down.
KNOWN BUGS
The AM regulator 2SC1419
is WEAK.
Unsolder it and toss it in the trash.
Replace
it with a GE-66, ECG-152 or a NTE-152.
Relay buzzes on
SSB, no am transmit, lights go dim, or the fuse pops sometimes?
Replace C179 ( a 2.2uF 25v tantalum cap located near finals) with a
standard 2.2uF electrolytic capacitor.
PAY ATTENTION to the "+" and "-"!!!
@DréCB/19MIR000=27.805Mhz./USB&6635Khz./LSB@