KSB2 with HM-7 mic question

[TJ Campie]

Thought of something else I ran into last night - I did not have any 820 Ohm
resistors to install on the config connector when wiring up for my Icom HM-7
microphone so I used a 1.1k - what are the effects of using a larger value?
Should I try to find/make an 820 Ohm resistor or does it matter?

TJ W0EA
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[Don Wilhelm-4]

Tom,

That microphone has an internal amplifier, and the resistor acts as a
collector load resistor.  I would guess that anything from the
recommended 820 ohms up to about 2k would work, but I can't say for sure
since I do not have data on the current drawn by the amplifier from a 5
volt supply.

If your microphone works, leave it as-is.  If it does not (or results in
a distorted signal), then change the resistor when you can get one.

73,
Don W3FPR

On 9/13/2011 12:22 PM, TJ Campie wrote:
> Thought of something else I ran into last night - I did not have any 820 Ohm
> resistors to install on the config connector when wiring up for my Icom HM-7
> microphone so I used a 1.1k - what are the effects of using a larger value?
> Should I try to find/make an 820 Ohm resistor or does it matter?
>
> TJ W0EA
>
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