STOCK MIC OR PRE-AMP (POWER) MIC?
(AND WHAT'S THE DIFFERENCE)
After buying a CB radio and antenna system, the first accessory that many of us choose to customize our radios, is an after market microphone. While some operators wait until they're told that their audio quality is lacking, many skip the audio checks and go directly to the webpage featuring microphones.
Going back to my first year of CB radio I was more or less ignorant of these choices and used the microphone that came with the radio. My Comstat 23 had the little tear drop "LRE" hand mic, and my Johnson Messenger 124 came with EFJ's standard hand mic as well as their non-amplified Johnson desk microphone. I liked the desk mic because it was easier to use in the shack, sitting on the desk with the 124 right behind it.
Whenever signal reports came about I always got decent comments about my transmitted audio, and except for gazing at the after market microphones in my Lafayette or Henshaws catalogs, I never felt the need to "accessorize".
If you've ever looked at the old radio advertisements in S9, CB Radio, or CB Horizons it's possible you noticed that most of the stock hand mics looked identical, except for the radio manufacturer's name plate being different - these microphones were usually made by the top 3 microphone manufacturers: Turner, Astatic, or Shure, so it was easy to see why their re-branded hand microphones sounded so good. Eventually this co-existence between CB radio and microphone manufacturers came to an end when the radio companies opted to import less expensive mics from Japan.
My adventures with microphones and audio quality began after I traded some gear for a Realistic Navaho TRC-23b AM base station.
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| PICTURED: TRC-23C. THIS LOOKED IDENTICAL TO THE 23B |
This was a no-frills / starter base station which would live on as the TRC-30 series (same box, but the 3 control knobs are on the left side of the radio vs. right).
It's signal reports were always good, but I was consistently told that my voice sounded like I was in a tin can (i.e. - Tinny). From that point on I began to search for a solution.
Initially I made a pre-amplified compression circuit to eliminate the tinny sound. The kit, which I got out of Popular Electronics, utilized a FET transistor as the heart of the design, but the amplification kit only made me sound like I was talking in a bigger tin can (I admit to burning up 2 FET's before finally getting wise to how fragile they were to static electricity).
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| IN THE PROCESS OF BLOWING ANOTHER FET |
I set this project aside when I picked up an E.F. Johnson Messenger 124. Both hand and desk microphones sounded great, and I was a happy camper once again.
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| THE EFJ MESSENGER 124 WITH EFJ DESK MIC |
For those of you who have read my written gibberish over the last 28 years you know what radio I picked up next, but for everyone else's knowledge, the lure of Single Sideband (SSB) snagged me, and like a starving fish that swallowed the hook, I purchased my first AM/SSB base station - Midland's 13-880B
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| MIDLAND 13-880B AM SSB BASE |
It was used, had the cigarette scent which most used radios of that period came with, and a stock hand microphone. There was only one other in our group of teens who had a Sideband radio so one day in school we arranged a Sked to meet up on channel 16 LSB. Compared to AM, his signal was stronger - and he had plenty of loud, crisp audio. When it was my turn, the signal report back to me wasn't stellar - My signal was slightly better than what he was accustomed to on AM, but my audio was tepid (i.e. - he said my audio "sucked"). After finding out I was only using a stock hand microphone, he advised me to get a Turner "Super Sidekick", because, "It was made for Sideband".
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| TURNER SUPER SIDEKICK ADVERTISEMENT (complete with Ozzy Osbourne lookalike) |
I sold my TRC-23B to a kid far enough away to where he wouldn't be a nuisance and used that money to order a Super Sidekick from the dealer in Boston. One week later when checking my P.O. Box for QSL cards I found a slip of paper indicating I had a package behind the counter. An hour, and several burned fingertips later my new Turner microphone was wired for the Midland...
After successfully lying about having all my homework done, I phoned my friend and asked if he could jump on 16 lower for a few minutes for a quick report. Without thinking twice about it he too lied to his mom as well, and within a few minutes I heard him calling me on SSB.
Not knowing where to set the volume control I only turned it clockwise slightly and asked him how I sounded - "Clear but low audio", he replied. Moving the knob mid-way I asked him again "How do I sound now". My memory isn't perfect, but his reply was akin to: "WOW - Your signal's almost twice what I see from you on AM and your audio is really banging". This was a watershed moment for me because I now realized how important audio became when talking on Sideband.
It wasn't because the Super Sidekick was advertised as a Sideband microphone, it was due to the amplifier circuit in the microphone. I would later get into mics with speech compression, but that's another story. Scrolling up to the top of this post I realized how much I digressed from the original title, so not wanting to be accused of the 'ol "Bait-N-Switch", here is the original article from S9 CB Magazine:
[CLICK ON IMAGE TO ENLARGE]
For further information on those great Turner microphones, refer to my blog post from last year - "The Turner Microphone Story"
I'll try to squeeze another post in this month (July) to make up for a silent June. Always remember to check the audio streams I post (Top Right of Blog) because I refresh them with new clips even if I'm not writing anything :)
73
Woody
