[1000mp] Advice on Mic Settings, Please

[Tod - Minnesota]

Rod's information is good advice for AM.

I find much the same thing with respect to settings for SSB.
MIC at about 9 and COMP at about 9, RF at about 2 o'clock
(when driving an ACOM linear).  

I truly agree with this statement of Rod's "..I've found
that using more compression is NOT productive in DX
pileups... having a clean crisp signal seems more effective
than a louder-but-muffled one."

With the ARRL DX Test coming up I would like to suggest to
DX stations that they check their MIC and compression
levels. Every year I struggle to comprehend what some of the
guys are sending on SSB because they have cranked the MIC
gain too high and also the compression too high. The result
is truly awful muffled and indistinct audio. The fellows who
have the audio set to be crisp really get quick QSO's and
lots of them.

As a rule of thumb, your Bird watt meter or similar watt
meter will show peaks (needle readings) about 1/10 of the
actual peak power output when there is no compression. With
heavy compression (too much in my opinion) that might
increase the power to show peaks 1/5 of the actual peak
power. For goodness sake do NOT set your controls so that
you see meter peaks as high as 1/2 of what you want as the
peak power -- you will almost certainly be splattering on
the band!.

Tod, KØTO





> -----Original Message-----
> From: 1000mp-bounces at mailman.qth.net 
> [mailto:1000mp-bounces at mailman.qth.net] On Behalf Of Rod
Elliott
> Sent: Thursday, January 06, 2005 12:26 AM
> To: 1000mp at mailman.qth.net
> Subject: Re: [1000mp] Advice on Mic Settings, Please
> 
> Robert...
> 
> 1. Connect the rig to a dummy load, then POWER on.
> 2. Set the voice processor (PROC button) off.
> 3. Set the METER VCC/MIC button to MIC. This will display
the 
> audio level in the transmit audio circuits.
> 4. Speak into the mic using your normal "radio" voice. Set

> the MIC gain control so the bar graph just hits the 
> right-hand side on occasional voice peaks. Leave the MIC
gain 
> at that setting unless you change your microphone. (On my
MP 
> with a Heil Pro-Set HC4 mic, this puts the MIC control at
9 
> o'clock) 5. Then adjust the RF PWR control so the PO bar 
> graph just hits 100 watts on voice peaks. (On my rig this 
> puts the RF PWR control at 3 o'clock)
> 
> With those settings, indicated power out (PO) should
average 
> 25 watts or less, and just make it to 100 watts on peaks. 
> Your ALC readings will just make it to the right-hand side
of 
> the red bar on peaks. All will be well... 
> you will have excellent audio quality and no splatter
(unless 
> you start shouting).
> 
> I know that 25 watts average sounds depressing, but a 6 dB

> peak/average ratio is typical for normal speech.
> 
> So what about the voice processor? As you know, it's
function 
> is to compress the dynamic range of your audio so as to 
> increase average power. 
> Like all good things, that comes at a price... with too
much 
> compression, fidelity and intelligibility suffer.
> 
> I like to use a little processing... just enough to help
the 
> ALC limit drive when I shout, but not enough to degrade
audio 
> quality. With the above settings, my setup is:
> 6. Set the PROC button to on.
> 7. Set the PROC control to maximum counter-clockwise 8.
Set 
> the METER ALC/COMP button to COMP 9. Talking in your
normal 
> voice, increase the PROC control setting until you get no 
> more than 2 or 3 dB compression on voice peaks. (On my MP 
> this puts the PROC control at 10 o'clock)
> 
> Once the mic and processor are is set up that way, I never

> have to change them. I get lots of "great audio" reports,
and 
> never a splatter complaint. 
> BTW, I've found that using more compression is NOT
productive 
> in DX pileups... having a clean crisp signal seems more 
> effective than a louder-but-muffled one.
> 
> Hope this helps...
> 
> 73
> Rod Elliott VE3UW
>