President George agc overload fix

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dt307
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President George agc overload fix

Post by dt307 » 24 Mar 2020, 14:23

you all know the George is a stunning radio but with agc overload issues and as yet i aint seen any info about a fix.

I have a simple fix for this that involves adding a non smd part to the solder side of the board but its across a smd part.

Test results are looking very good and i have Keiron also testing the mod and waiting feedback before i let it loose in the wild.

If any 1 has a president George and in a position to do some before and after tests with strong stations and you can solder good and have min temp controlled iron,liquid flux and half a brain ......please pm me.

For reference on a scale of 1-10 in agc overload i would rank the George in std form a 3 (yes its that bad) and a cobra 148 gtldx mk2 as a good 9.

And with this mod i rank a modded George to about a 7-8.

Its not perfect but i have to weigh in ease of mod vs end result and to get it to the same level as say a 148 the mod will be quite hard.

My own testing has found a local station 5 miles away on a 148 std power was overloading the George front end real bad but when modded he can run a kl203 and still be perfect.
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cb4ever104
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Re: President George agc overload fix

Post by cb4ever104 » 25 Mar 2020, 15:28

Looking forward to hearing more about this Chris .

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Mudslinger
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Re: President George agc overload fix

Post by Mudslinger » 25 Mar 2020, 18:22

Excellent news. Unfortunately both of the George's I have owned were sold due to this very issue.

I am assuming that the fix is similar in principle to the one on the Jackson?

Another radio which suffers from AGC overload is the Grant 2, or at least the ones I owned did...
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Re: President George agc overload fix

Post by dt307 » 26 Mar 2020, 02:50

Mudslinger wrote:
25 Mar 2020, 18:22
Excellent news. Unfortunately both of the George's I have owned were sold due to this very issue.

I am assuming that the fix is similar in principle to the one on the Jackson?

Another radio which suffers from AGC overload is the Grant 2, or at least the ones I owned did...
as for jackson yes and no ......yes we modding the agc circuit , but no its done different as its smd i could not put out a mod involving changing smd parts due to the risk of damage to radios.....adding a part that is a std size 1/4 watt resistor is fine .

as for the grant 2 i have not had 1 or the newer prem version but i have the service manuals for both and just had a quick squint and the changes they made to the agc circuit but strange as it may be i just bought a grant 2 early version and should be here soon so that will get some love as well.

dont help the jackson and george and grant 2 all use the same type of circuit but all different....quad op amp in tri mode ,or dual op amp for agc and squelch ect ......but if was all simple where would the fun be in that.

like i said im after an easy fix for every 1 that gets the radio working miles better than a std 1 without having to remove smd parts .....and i think i am there just awaiting more testing
163dt307-chris




“I fear the day that technology will surpass our human interaction. The world will have a generation of idiots.”
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