You've ALMOST Talked Me Into Taking the Export Plunge!

Discussion in 'CB Radio Forum' started by The Gryphon, May 29, 2014.

  1. jessejamesdallas

    jessejamesdallas Road Train Member

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    But the guy here that started this thread, said he was looking for a "BIG RADIO"...Going by that, and the fact he's been looking at the Generals, one can only assume He's looking for a radio with "Big BOOMING AUDIO"............and not some want-to-be 10-meter beginner HAM rig...(which is all the 2950 is)
     
    poppapump1332 Thanks this.
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  3. BigBearNY

    BigBearNY Light Load Member

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    I think someone here already said... RCI and General come from the same place... Tun he audio up it's a BIGGER, BETTER radio.
     
  4. jessejamesdallas

    jessejamesdallas Road Train Member

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    just because they come from the same place, doesn't mean they have the same audio...
     
  5. Bashnya

    Bashnya Light Load Member

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    Whatever makes you happy. Just make sure that big-finaled radio can breath. Heat kills, and quickly.

    I'm with Jesse. If you want more power, go with an external amp. That way if the amp quits, you still have the radio. When that hiwatt monster goes into meltdown, then you have nothing.

    But it's your money. Whatever floats yer boat...
     
    handlebar Thanks this.
  6. handlebar

    handlebar Heavy Load Member

    What Bashnya said........ Start with a decent stock radio that performs to specs (not strangled for every last fraction of a watt on output meter and then finding one of the myriad ways of causing it to overmodulate, or echo forever). Once you've got a clean radio, a resonant antenna working against an adequate counterpoise, and decent local performance, *then* add an external kicker -- but only if you're hearing folks who can't hear you clearly.
    If your system were symmetrical with everyone else, meaning you can hear about as far as you can be heard, then simply adding an extra hundred or more watts to the output will turn you into an alligator station: all mouth and no ears. If you can no longer hear the guy you were speaking with just minutes ago, turning on an amp will must frustrate him because he can hear you but you still can't hear him, *plus* you'll be making the channel unusable for everyone else as you become, for all intents and purposes, a broadcaster, with no realistic intent in hearing replies.

    BTW, someone mentioned the popular RM Italy KL-203p amplifier. Despite their published specs of being able to handle around 10 watts input, extensive research by folks who are at least an order of magnitude smarter than I am (but with similarly equipped professional service benches) have fairly universally determined that 1.0 to about 1.5 watts is the *maximum* input power they can take without having their outputs go horribly non-linear. Better to have your deadkey turned down (after having everything else in the radio re-aligned to spec) and avoiding the all-too-common false bait of "maximum swing" on your signal. You can only increase an a.m. carrier ("deadkey") by around 50% (by adding 25% from each sideband) and keep the signal linear.

    Also, as Jesse and Bashnya suggest, if your amp goes out, you can always just disconnect its interconnecting cables and run barefoot until the amp is either fixed, sold off, or thrown away.

    If it weren't for inexpensive, peak-reading wattmeters with user-accessible "max signal" adjustments, and instead more oscilloscopes and spectrum analyzers in use by experienced technicians who know the theory and their proper use, there would be a lot more clean signals on the band -- and fewer channels being wiped out by overmodulated alligator stations.
    Hope that helps. This comes from over 50 years as a licensed ham and over 40 years as an FCC licensed commercial radiotelephone tech.
    73
     
    The Gryphon Thanks this.
  7. The Gryphon

    The Gryphon Heavy Load Member

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    Once I have my deadkey turned down, if my amp goes out will I still be able to use the radio with a 1 watt deadkey?

    Won't it then be 1/4 as powerful as it was stock and thus probably only able to be heard the length of my truck away, if at all?
     
  8. handlebar

    handlebar Heavy Load Member

    Sure, having only 1 watt out will limit your range somewhat from 4 watts -- around half an S-unit. Ideally whoever modifies your deadkey can offer you either an otherwise-useless toggle switch or a "Delta Tune" or some such otherwise useless "feature" reassigned to allow the massive QRO of 4 or 5 watts when engaged. If there will *usually* be an RM amp attached, I'd ask the tech to wire a pretty bright/obnoxious lamp somewhere where it won't blind you but *will* tell you that your "little radio" is putting out too much for the amp, once it's back in its rightful place. The huge "Oil pressure lost" lamp on the dashboard of a fuel dragster comes to mind, but is likely to give you a suntan by the time you stop for coffee ;) You could even hang some sort of lockout/padout tag on your mic cord, of the sort when people are working on a live electrical circuit and want to make sure it doesn't get engaged until the last tag is taken off by its owner.

    Lotsa simple ways to do it. But I most strongly suggest not taking the owner's manual at its word about its input tolerances. My bench costs more than a lot of 2014 model cars, and I've gotten to watch on a spectrum analyzer when the input on a -203 is run up to about 15 watts (RM Italy reimbursed us, as the test was done with their approval). Nice folks to work with, by the way.

    HTH
    73
     
    The Gryphon Thanks this.
  9. The Gryphon

    The Gryphon Heavy Load Member

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    I was thinking that maybe the tech could make the CB/PA switch a Hi/Lo switch with the Hi being stock and Lo being the turned down deadkey.

    Is that doable and does it make sense?

    I don't have a PA hooked up so I never use that switch.
     
  10. Ridgeline

    Ridgeline Road Train Member

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    Of course it is doable, I've done it on several radios, but I know what I'm doing and a lot of "techs" don't.
     
    Big_m, The Gryphon and handlebar Thank this.
  11. handlebar

    handlebar Heavy Load Member

    Ditto -- what he said. Even with a small PA speaker plugged into the rear apron, they're about useless unless you're indoors and there are no other sounds -- like running engines -- before they're heard. Probably useful to clearly label the new functions on the switch's escutcheon. Also, if you're able (or your tech is) to change the color of the backlighting or *something* to warn you that the radio is running at its massive 4 watts or so, just to help prevent overdriving your amp.

    Ridgeline is one of those folks whom I'd trust to perform the mod correctly and without butchering the other (and unrelated) adjustments. There are several folks here. Just look for someone local who has a bench that looks like some from Mission Control at NASA and can explain their use.

    If you stumble across a "tech" whose bench is populated only by a Rat Shack SWR/power meter (or even a Dosy with a huge dial), an assortment of metal screwdrivers, and a pair of diagonal cutters, nobody would fault you if you left skidmarks on the floor enroute to the exit :)

    Good luck & 73
     
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