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so there is an intermittent problem that I thought I solved with a recap. but apparently not. im thinking it might be a bad driver but i want to make sure first. power drops, audio flutters, eventually comes back but about half of it's power output. odd stuff. before it started acting up again...

eventually this thread will be canned and I will make a master 19gtl hotrodding checklist thread with a mosfet.

what I did was put a 47k ohm in the r37 spot, and 10uf on c51. i also replaced the 5.6k at r31 with a 3.3k to increase the mic gain. so we're up from 10w PEP to a nice clean 18-19 from a 5wdk on a stock final. so i think that's what im gonna go with on this weekend project. i havent even...

is it c51, c48, or both for the release delay cap? coming soon: a 19gtl hotrod mosfet thread

yea thats what i figured. i ordered some 450 ohm and im about to make some coax baluns/line transformers for either end of the run. also got myself a dpdt knife switch so if theres a lot of lightning the whole system will be shunted to ground

what is the impedance of two 75 ohm as a coaxed balanced feed? i've read about ppl doing it before.

ah yea. 150 ohm. i'd be interested due to the coaxial nature of each lead how loss would stack up compared to 300, 450, or 600. I imagine it'd be good as a 1/4~ impedance line transformer in the very least.

a balun like this one I posted for monoband or a torroidal for multi-band will improve snr. kills common mode currents. im looking to get the best of both worlds here by using coax in the house but balanced outside

digging up old bones here. 150' of 8x for me loses 20-25 watts between a 1 and 1.5 swr per 150'. im a working class guy so doing LMR for that run is not in the budget. so my plan is to make my own, around 450-500 ohm balanced feed, with a monoband feedline balun/1/4wave line transformation...

I personally wouldn't bother. i'd hold onto em for a JIC situation.

ok revisiting this one. changed back the diodes to stock, still have no RX meter movement, TX meter is working, and I reflowed the caps that were swapped in that area. hmm, what else did I mess up? i don't want to return this with no rx meter

i've done it. don't really remember how, but i've done it. it was cool for sh1ts and giggles. im not anti-final upgrade. sometimes that 10 extra peak watts might only be a .003% of an s-unit, but sometimes it is exactly what the kicker wants

the pot is intact, theres the 8.6v leading to it.

mosfet tabs are the same as the drain so running without an insulator would cause a ton of problems

just tacked 820ohm across c91 (changed to 33uf). that did the trick. clean on adjacents, fast and robust. thanks again andy, and if we can get this thread pinned so everyone knows how to make the meter do the bit without making the neighbors hear the ghost watts on the (very common) cobra 25...

c88? the .1 going from the AMC to the mic amp on the 29 schematic is 1uf on the 25's c90. unsure how high I should take it if at all.

ah ok. so yea, i'll leave c70 (98 on the 25) and tack in a resistor to see what happens. never seen power drop like that from lowering the release cap on any other radio. only the 25/66

thank you for the info. so it appears on the 25 it's c98 that i should put a 1k in place of. should i leave the 33uf in c91 or change back closer to stock?

ok so off of andy's advice that limiter release cap in these rigs get changed on the 29s and it makes the wattage ABSOLUTELY SLAM but when i try it on the 25, it supresses the modulation bigtime. looking at the schematic im not really seeing a difference in the layout of the 2 limiter sections...

the xlr is a different animal