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I also replaced the AM Regulator and the two transistors on the aluminum panel on the back.

Two white LED's in the meter looks outstanding and is cheep to do! Removed the red transmit light altogether and used its mounting location for the second white LED. The red TX light obscures the meter movement when transmitting = annoying to me.

A LOT if useful info on unit_399's site; I used the mod to improve the AM audio by adding an electrolytic cap and a 1N914 diode to make the AM modulation better. Also replaced the 2SC1306 with a 2SC2166/driver:
http://unit399.wixsite.com/858ssb

Put in Schottky diodes in too.

Took out that nasty 5 pin DIN plug and installed a standard 4-pin male plug with the standard Cobra wiring.

Used Klondike Mike's cap kit to recap the radio. Also replaced all of the tantalum caps.

Radio now will dead key 4w and swing 30w with Xit13's MOSFET mod. A cheap and very useful mod! Cost about a nickel to roll your own biasing device and the IRF-520 MOSFET cost about a buck:
http://www.worldwidedx.com/threads/mosfet-conversions-for-upd858-and-mb8719-boards.95853/

You will find the C179 cap close to the front/left corner of the main board close to the right of the final/driver transistors and right next to test points 1 & 2.

<blockquote data-quote="Robb" data-source="post: 584760" data-attributes="member: 8446">I also replaced the AM Regulator and the two transistors on the aluminum panel on the back.Two white LED&#039;s in the meter looks outstanding and is cheep to do!&nbsp; Removed the red transmit light altogether and used its mounting location for the second white LED.&nbsp; The red TX light obscures the meter movement when transmitting = annoying to me.A LOT if useful info on unit_399&#039;s site; I used the mod to improve the AM audio by adding an electrolytic cap and a 1N914 diode to make the AM modulation better.&nbsp; Also replaced the 2SC1306 with a 2SC2166/driver:<a href="http://unit399.wixsite.com/858ssb" target="_blank">http://unit399.wixsite.com/858ssb</a>Put in Schottky diodes in too.Took out that nasty 5 pin DIN plug and installed a standard 4-pin male plug with the standard Cobra wiring.Used Klondike Mike&#039;s cap kit to recap the radio.&nbsp; Also replaced all of the tantalum caps.Radio now will dead key 4w and swing 30w with Xit13&#039;s MOSFET mod.&nbsp; A cheap and very useful mod!&nbsp; Cost about a nickel to roll your own biasing device and the IRF-520 MOSFET cost about a buck:<a href="http://www.worldwidedx.com/threads/mosfet-conversions-for-upd858-and-mb8719-boards.95853/" target="_blank">http://www.worldwidedx.com/threads/mosfet-conversions-for-upd858-and-mb8719-boards.95853/</a>You will find the C179 cap close to the front/left corner of the main board close to the right of the final/driver transistors and right next to test points 1 &amp; 2.</blockquote>

[QUOTE="Robb, post: 584760, member: 8446"] I also replaced the AM Regulator and the two transistors on the aluminum panel on the back. Two white LED's in the meter looks outstanding and is cheep to do! Removed the red transmit light altogether and used its mounting location for the second white LED. The red TX light obscures the meter movement when transmitting = annoying to me. A LOT if useful info on unit_399's site; I used the mod to improve the AM audio by adding an electrolytic cap and a 1N914 diode to make the AM modulation better. Also replaced the 2SC1306 with a 2SC2166/driver: [URL]http://unit399.wixsite.com/858ssb[/URL] Put in Schottky diodes in too. Took out that nasty 5 pin DIN plug and installed a standard 4-pin male plug with the standard Cobra wiring. Used Klondike Mike's cap kit to recap the radio. Also replaced all of the tantalum caps. Radio now will dead key 4w and swing 30w with Xit13's MOSFET mod. [I]A cheap and very useful mod![/I] Cost about a nickel to roll your own biasing device and the IRF-520 MOSFET cost about a buck: [URL]http://www.worldwidedx.com/threads/mosfet-conversions-for-upd858-and-mb8719-boards.95853/[/URL] [COLOR=#ff4d4d]You will find the C179 cap close to the front/left corner of the main board close to the right of the final/driver transistors and right next to test points 1 & 2.[/COLOR] [/QUOTE]

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