picture of 858 pll extra channel mod.

[Carl]

working on a 139xlr and I can't get it to accept extras for the life of me. anyone have a picture of a ssb 858 chassis (trace side) so I can make sure I'm doing the right pins.

Sent from my SAMSUNG-SGH-I997 using Xparent Blue Tapatalk 2

 

[sonoma]

see if this link will help you do it.


Realistic TRC-458 26.045 to 30mhz expansion

 

[giboni]

see if this link will help you do it.


Realistic TRC-458 26.045 to 30mhz expansion

The thread is not that old.

The wayback machine does not have a copy of the webpage link posted above.

I have a working Trc457 Navaho that I just recapped and aligned.

I would like to expand the frequency coverage. 80 up 40 down without buying an expensive kit if at all possible.

Maybe the original poster copied the web page ?

Best 73s John

 

[unit_399]

try this ... pages 23 and 24: http://www.cbtricks.com/radios/realistic/trc_449/graphics/realistic_trc_449_sm.pdf

and this: http://bigstrap.tripod.com/

73s.

- 399

 

[giboni]

try this ... pages 23 and 24: http://www.cbtricks.com/radios/realistic/trc_449/graphics/realistic_trc_449_sm.pdf

and this: http://bigstrap.tripod.com/

73s.

- 399

Hi 399,

Thanks for taking the time to post the Links.

I actually found the first one after posting here.

The web page author states raising the Trc 457 power Supply to 14.8 Volts ?

Has to be a misprint.

The original 3300uf in my Trc 457 was Bulging. I replaced with 5 x 1000 uf. All I had new.
Replaced the small one with a new 220 UF. When I get my order will re-replace with Low leakage 125c 4700 mfd.

Did the 15uf & diode swap.

Did the Shotky swap.

I am not satisfied with the modulation percentage average Only %60 peak 70.

What about this Mod from a Defpom page. Will this perhaps get this close to 100% modulation.
As an SSB rig. I will not chop out the AM limiter.
_________________________________________________________
(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.
__________________________________________________________
Would it make a difference if I swap out 2SC1419 to a NTE 152? & Or swap the
upC1156H & replace with Toshiba TA7222AP
__________________________________________________________
For the extras what about this. Just received the RS switch.

This is from Secret CB Vollume 9 page 8-11 Hosted by CB tricks You can download the complete PDF. upd 858 rotary switch expansion
__________________________________________________________

 

[unit_399]

Not a misprint. 14.8 is good. The defcom mod will eliminate the speech clipper circuit and will actually reduce average modulation.