ok. 1 down now on to the next. bought a irf 520 kit on ebay. want to put it in my old 29 ltd which has a blown final. came with instructions but to say the least they leave alot to be desired.
MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. Remove C53 and solder it across C59. In C53's place solder a 3.3k resistor. Remove C 61 and solder it across C62. Remove C126. Remove R55 amd solder a 22pf cap in its place. Remove the slug from L14. Replace C71 with a 33-47uf cap. Turn VR4 (AMC) counterclockwise fully. Gently spread L13 and L12 and tweak the spreads for best PEP when modulated. Tweak L20 and L17 for best PEP when modulated. After tuning is finished, set VR4 to half-way.
Note: Older 29's (LTD and GTL) use the same basic procedure, but instead of re-using the caps, place a 100pf across C62, a 68pf across C59, and 22pf across the spot where you removed R55.
i only see one hole for r56. the other hole says L23 maybe..hard to see. is that where the other end of the diode goes? ive also seen the same mod with many less parts changed out. ive also seen some that say not to remove the L14 slug. i have the parts and a soldering iron and im ready to go. let me know if you can simplify this as im a simple man...pics would be very helpful also. help me out here, im on a role
MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. Remove C53 and solder it across C59. In C53's place solder a 3.3k resistor. Remove C 61 and solder it across C62. Remove C126. Remove R55 amd solder a 22pf cap in its place. Remove the slug from L14. Replace C71 with a 33-47uf cap. Turn VR4 (AMC) counterclockwise fully. Gently spread L13 and L12 and tweak the spreads for best PEP when modulated. Tweak L20 and L17 for best PEP when modulated. After tuning is finished, set VR4 to half-way.
Note: Older 29's (LTD and GTL) use the same basic procedure, but instead of re-using the caps, place a 100pf across C62, a 68pf across C59, and 22pf across the spot where you removed R55.
i only see one hole for r56. the other hole says L23 maybe..hard to see. is that where the other end of the diode goes? ive also seen the same mod with many less parts changed out. ive also seen some that say not to remove the L14 slug. i have the parts and a soldering iron and im ready to go. let me know if you can simplify this as im a simple man...pics would be very helpful also. help me out here, im on a role