You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
The Feb 2025 Radioddity Giveaway Results are In! Click Here to see who won!

Reply to thread

Message

Update on this. After closer look with the scope probing around, it appears that I have proper drive signal, Bias voltage, and switching (RX/TX).

The problem appears to be that if you replace the RD16HHF1 with a IRF520, you have to retune the output coils. I did not want to mess with that, will just order a handful of RD16HHF1's and when they get here, try replacing it, if a minor retune is necessary will do that. I think I'll add some sort of heatsink to the back of the radio, using a longer screw, some thermal compound, and a sil-pad insulator (or Mica insulator), since the RD16HHF1 transistors seem to have a reputation for being a little on the fragile side, the extra heat dissipation should take care of most of that issue.

Would have been nice if they would have designed this radio with a little better receiver, and dual RD16HHF1 output transistors for longevity sake. Still cannot believe after all this time, there is not a schematic available for this rig... The only reason I even want to repair it, is because it's in pristine condition, everything works fine, and I kinda like it's layout and functions.

<blockquote data-quote="443" data-source="post: 773955" data-attributes="member: 15034">Update on this.&nbsp;&nbsp; After closer look with the scope probing around, it appears that I have proper drive signal, Bias voltage, and switching (RX/TX).&nbsp; The problem appears to be that if you replace the RD16HHF1 with a IRF520, you have to retune the output coils.&nbsp; I did not want to mess with that, will just order a handful of RD16HHF1&#039;s and when they get here, try replacing it, if a minor retune is necessary will do that.&nbsp; I think I&#039;ll add some sort of heatsink to the back of the radio, using a longer screw, some thermal compound, and a sil-pad insulator (or Mica insulator), since the RD16HHF1 transistors seem to have a reputation for being a little on the fragile side, the extra heat dissipation should take care of most of that issue. Would have been nice if they would have designed this radio with a little better receiver, and dual RD16HHF1 output transistors for longevity sake. Still cannot believe after all this time, there is not a schematic available for this rig...&nbsp; The only reason I even want to repair it, is because it&#039;s in pristine condition, everything works fine, and I kinda like it&#039;s layout and functions.</blockquote>

[QUOTE="443, post: 773955, member: 15034"] Update on this. After closer look with the scope probing around, it appears that I have proper drive signal, Bias voltage, and switching (RX/TX). The problem appears to be that if you replace the RD16HHF1 with a IRF520, you have to retune the output coils. I did not want to mess with that, will just order a handful of RD16HHF1's and when they get here, try replacing it, if a minor retune is necessary will do that. I think I'll add some sort of heatsink to the back of the radio, using a longer screw, some thermal compound, and a sil-pad insulator (or Mica insulator), since the RD16HHF1 transistors seem to have a reputation for being a little on the fragile side, the extra heat dissipation should take care of most of that issue. Would have been nice if they would have designed this radio with a little better receiver, and dual RD16HHF1 output transistors for longevity sake. Still cannot believe after all this time, there is not a schematic available for this rig... The only reason I even want to repair it, is because it's in pristine condition, everything works fine, and I kinda like it's layout and functions. [/QUOTE]

Top Bottom