Is it necessary to have a radio aligned or checked after replacing finals or installing a max mod?
-
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.
Replacing finals
- Thread starter 743SEPA
- Start date
Depends on radio. in SSB rig bias need to be checked/adjusted.
For maxmod, nope.
Mike
For maxmod, nope.
Mike
When a final transistor fails, it tends to short internally. Frequently this causes the 12-Volt DC power on the final transistor's output collector to come shooting out the base terminal, the input side.
Sometimes parts in the final's input circuit will be damaged. Might only be a 10-ohm resistor that gets scorched, like in a Cobra 29LTD. Or if it's a sideband radio the bias diode, bias trimpot and a resistor or two will all get blown out.
In some radios, like those made by RCI the modulator transistor can get popped as well. The Max-Mod may require a notch to be ground off the lower-left corner of the Max-Mod's plastic package to clear the anchor lug to the rear from it.
The new final won't work properly until all collateral damage is repaired as well.
Just replacing the final alone might fix a problem. But only if the final transistor is the only component that got damaged.
What kind of radio is this? Makes a big difference.
Installing a MaxMod should not affect any adjustments, if the radio was working normally before the swap.
73
Sometimes parts in the final's input circuit will be damaged. Might only be a 10-ohm resistor that gets scorched, like in a Cobra 29LTD. Or if it's a sideband radio the bias diode, bias trimpot and a resistor or two will all get blown out.
In some radios, like those made by RCI the modulator transistor can get popped as well. The Max-Mod may require a notch to be ground off the lower-left corner of the Max-Mod's plastic package to clear the anchor lug to the rear from it.
The new final won't work properly until all collateral damage is repaired as well.
Just replacing the final alone might fix a problem. But only if the final transistor is the only component that got damaged.
What kind of radio is this? Makes a big difference.
Installing a MaxMod should not affect any adjustments, if the radio was working normally before the swap.
73
But a side note here and not to hi-jack, the Max-Mod won’t work in a 497HPC. Been there and done that, not as a drop-in replacement. Myself and Key CB shop know this first hand.
Otherwise, I agree 110% with Nomad. Check supporting components.
Otherwise, I agree 110% with Nomad. Check supporting components.
-
@ BJ radionut:I am beginning the packing process...XENIA bound Going "Lite": this year....2 items for sale...Rig #1 = FT-920/Gud to Ex condition/Hand Mike/pwr cord/manual (NO BOX) ... #2 = My 1 owner FT-950....EX condition...Original Shipping Double Box/Factory Manual/Never used hand mike...Booths 9107-9111...Ya'al come by say hello...
-
@ BJ radionut:
Incoming Region Produces X3 Solar Flare May 15, 2024 @ 14:55 UTC Another major solar flare, but this time from an active region just beginning to turn into view off the east limb. It is possible that the group responsible is old AR 3654 from the previous rotation. The latest flare, an X2.99 event just peaked at 14:38 UTC (May 15). Stay tuned -
-
-
@ ButtFuzz:Please advise me to what is a good replacement mic for my SR-497HPC... Answer: 497 is "wired like Cobra", so many choices available. That radio does not need a power mic, so purchase a stock "coffin style" mic with a decent cord, like the ones that Astatic uses. The Superstar DM-507 is my go-to. https://www.ebay.com/itm/3050474478...adANq91JSiEEnz8EGqPJRBloTgEyaVsBoCtoMQAvD_BwE $12.99 + .99 cent shipping.