The install details:
Cobra 29 classic with RFX-75 professionally installed, set to DK 15w and pep 80w. The radio is running the upgraded power chord straight to battery with an additional ground wire from mount to metal dash frame. Mic is a 636l.
Texas Star DX500v with upgraded power cables, (4gauge) straight to battery. Negative 4 gauge to battery and seat mount bolt.
Wilson 1000 magnetic mount, top of roof, centered.
Radio shack swr/power meter.
Good quality 6 foot coax used for jumpers.
All mounted in F250. Have ran bonding straps from cab to frame. (I have more strap ordered to bond the bed..etc..)
My SWR is at <1.5 channel 1 - 40 with linear off.
SWR goes to 3.2 or so with linear on.
The issue:
The radio without linear on sounds great and gets out good. Per radio shack meter, dead keys 20w with engine running, Volts=14. PEP 90-100
If I turn the linear full on, (NO variable), I get a high pitched wine, and talk back sounds diminished, also confirmed with a another driver, that my sound deteriorates with linear on.
If I switch on variable and turn knob just off full, the degradation goes away and the great sound returns, per RS meter- DK100-120 with PEP 450'ish
If the engine is off, I can go all the way with variable pot without degradation, but if engine is running, I have to back it back a bit.
Thoughts?
Rick
Cobra 29 classic with RFX-75 professionally installed, set to DK 15w and pep 80w. The radio is running the upgraded power chord straight to battery with an additional ground wire from mount to metal dash frame. Mic is a 636l.
Texas Star DX500v with upgraded power cables, (4gauge) straight to battery. Negative 4 gauge to battery and seat mount bolt.
Wilson 1000 magnetic mount, top of roof, centered.
Radio shack swr/power meter.
Good quality 6 foot coax used for jumpers.
All mounted in F250. Have ran bonding straps from cab to frame. (I have more strap ordered to bond the bed..etc..)
My SWR is at <1.5 channel 1 - 40 with linear off.
SWR goes to 3.2 or so with linear on.
The issue:
The radio without linear on sounds great and gets out good. Per radio shack meter, dead keys 20w with engine running, Volts=14. PEP 90-100
If I turn the linear full on, (NO variable), I get a high pitched wine, and talk back sounds diminished, also confirmed with a another driver, that my sound deteriorates with linear on.
If I switch on variable and turn knob just off full, the degradation goes away and the great sound returns, per RS meter- DK100-120 with PEP 450'ish
If the engine is off, I can go all the way with variable pot without degradation, but if engine is running, I have to back it back a bit.
Thoughts?
Rick
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