[ICOM] 751A: Favour, Please!

[D C *Mac* Macdonald]

The actual frequency of the transmitted CW signal

will ALWAYS be displaced from your dial frequency

on ANY rig.  The most common displacement is

around 1000 Hz.  Research done during or prior to

WW II indicated that the most responsive frequency

by the human ear is about 1020 Hz.

 

Usually, the alignment procedure for a transceiver

provides for setting that offset within a range of

audio frequencies.

 

Remember that if the signal were exactly zero beat,

the listener would hear NOTHING!

 

73 - Mac, K2GKK/5

(Since 30 Nov 53)

Oklahoma City, OK


 

> From: gswynar at durham.net
> To: icom at mailman.qth.net
> Date: Thu, 5 Nov 2009 12:59:57 -0500
> Subject: [ICOM] 751A: Favour, Please!
> 
> Good Day All,
> 
> I wonder if anyone reading this who has (A) an Icom 751A transceiver, (B) a
> dummy load, and (C) a digital frequency meter, might please do me a
> favour...?
> 
> Place the mode switch on CW, and tune the rig so that the dial displays
> exactly 7010-KHz: now, hold the CW key down, emit an actual signal into the
> dummy load, & note the frequency on the digital frequency meter.
> 
> What is the difference between what's displayed on the meter, & what the
> display shows on the rig itself...?
> 
> Mine here continues to transmit 2-KHz lower in frequency than the dial
> frequency---but only on CW. I've done all the frequency tests that I can as
> outlined in the service manual, & the doggone thing still malfunctions.
> 
> Many thanks, &
> 
> ~73!~ de Eddy VE3CUI - VE3XZ
> 
> 
> ----
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