[Milsurplus] headset for bc-221 frequency meter

[Al Klase]

Hutch,

That translates into 2000 ohms DC in "civilian" terms.  However, exact 
matching is not required, even a 600-ohm (impedance) headset will work 
OK, but won't be as loud.  An 8-ohm audiophile unit is not a good bet.  
The impedance of a headset, at 1KHz, will be roughly four or five times 
its DC resistance.

Regards,
Al

WA5CAB at cs.com wrote:
> Hutch,
>
> P-18 and P-20 are both 24,000 ohm.  Some BC-221 models were issued 
> with the 8,000 ohm HS-23 plus CD-307,-A.  Later production models were 
> issued with HS-30 and long Hi-Z cord CD-605 (8,000 ohm). 
>
> The P-18 and P-20 are pretty scarce.  The CD-605 is scarce but you can 
> build one from a CD-604 and CD-307 which are not so scarce.  The HS-23 
> is probably the most comfortable to wear.
>
> In a message dated 10/16/2007 10:39:50 AM Central Daylight Time, 
> olegerityincj at austin.rr.com writes:
>> Any one know what impedance is needed for a head set / or speaker for an
>> LM- series or BC-221 series frequency meter?
>> P-18 P-20

-- 
Al Klase - N3FRQ
Flemington, NJ
http://www.skywaves.ar88.net/