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I have too many working hours on this radio, too many parts have been replaced, dont get me wrong but the radio TX better than my TS940 the audio is so great. It has some issues on RX sometimes it has a popcorn sound it has a lot of corrosion's and jumpers parts, you know what parts I've replace because you know the parts, I feel like a mechanic just replacing the damaged parts but not what is causing the damage. You asked me about s403 switch from 1990 cobra to 88 and same results. I replaced R100 (6.8k) for 3.3k in order to get enough drive through the loop. I also replaced c88/c89 from 47pf to 33pf and it was worse. Then i was looking for 100pf but i didnt have it so i found 68 and it is more stable. I also replaced the varactors d35/d69, also I replaced L19(LA216) and cut 1 turn of the ferite cord. IC1 pin 10 of the PLL and tie it to pin 17. I used diode 1N4148 inline, cathode (banded side) goes to pin 17. I think this loop is not working for some reason. also I think theres a bypass cap on short somewhere. Also FT-1,R26/ R65/R66/R67/R69/R70 are on bad shape.

thanks for your help and tips! greatly appreciated, I read each paragraph 20+ times! good learning experience

<blockquote data-quote="Robalo" data-source="post: 627975" data-attributes="member: 1812">I have too many working hours on this radio, too many parts have been replaced, dont get me wrong but the radio TX better than my TS940 the audio is so great. It has some issues on RX sometimes it has a popcorn sound it has a lot of corrosion&#039;s and jumpers parts, you know what parts I&#039;ve replace because you know the parts, I feel like a mechanic just replacing the damaged parts but not what is causing the damage.&nbsp; You asked me about s403 switch from 1990 cobra to 88 and same results. I replaced R100 (6.8k) for 3.3k in order to get enough drive through the loop. I also replaced c88/c89 from 47pf to 33pf and it was worse. Then i was looking for 100pf but i didnt have it so i found 68 and it is more stable. I also replaced the varactors d35/d69, also I replaced L19(LA216) and cut 1 turn of the ferite cord.&nbsp; IC1&nbsp; pin 10 of the PLL and tie it to pin 17. I used diode 1N4148 inline, cathode (banded side) goes to pin 17. I think this loop is not working for some reason. also I think theres a bypass cap on short somewhere. Also FT-1,R26/ R65/R66/R67/R69/R70 are on bad shape.thanks for your help and tips! greatly appreciated, I read each paragraph 20+ times! good learning experience</blockquote>

[QUOTE="Robalo, post: 627975, member: 1812"] I have too many working hours on this radio, too many parts have been replaced, dont get me wrong but the radio TX better than my TS940 the audio is so great. It has some issues on RX sometimes it has a popcorn sound it has a lot of corrosion's and jumpers parts, you know what parts I've replace because you know the parts, I feel like a mechanic just replacing the damaged parts but not what is causing the damage. You asked me about s403 switch from 1990 cobra to 88 and same results. I replaced R100 (6.8k) for 3.3k in order to get enough drive through the loop. I also replaced c88/c89 from 47pf to 33pf and it was worse. Then i was looking for 100pf but i didnt have it so i found 68 and it is more stable. I also replaced the varactors d35/d69, also I replaced L19(LA216) and cut 1 turn of the ferite cord. IC1 pin 10 of the PLL and tie it to pin 17. I used diode 1N4148 inline, cathode (banded side) goes to pin 17. I think this loop is not working for some reason. also I think theres a bypass cap on short somewhere. Also FT-1,R26/ R65/R66/R67/R69/R70 are on bad shape. thanks for your help and tips! greatly appreciated, I read each paragraph 20+ times! good learning experience [/QUOTE]

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