Speaker muting on HW-101

[CyberGeezer]

Did the mod.  Works fine!  Thanks!!

73 de W2GERry

----- Original Message -----
From: "ejforwood Jerold Forwood" <ejforwood at MSN.COM>
To: <HEATH at LISTSERV.TEMPE.GOV>
Sent: Tuesday, June 18, 2002 10:09 AM
Subject: Re: Speaker muting on HW-101


There is a modification list on all sorts of improvements for the HW-101 by
Mark, WB8JKR.  You can find it under "MODS" at
http://members.tripod.com/~NRWILLIAMSON/index-2.html.  The first thing it
covers is converting to low-Z headphones.
73's,
Jerry, K0EJF
----- Original Message -----
From: CyberGeezer
Sent: Tuesday, June 18, 2002 7:42 AM
To: HEATH at LISTSERV.TEMPE.GOV
Subject: Speaker muting on HW-101

Anybody know where to get a set of old-time "communication headphones"?

The old-time ones were typically 1000 ohms per earphone or 2000 ohms for the
whole headset.  This apparently is the impedance the HW-101 expects to see
at the headphone jack.  (The manual is silent on this.  The schematic is
silent on the impedances of the two portions of the audio output transformer
secondary.)

When I plug in a new-fangled 8-ohm headphone the speaker does not mute
perceptibly.  I connected a 1K resistor to a headphone plug, plugged it in,
and the speaker muted (still audible, but barely).

73 de W2GERry

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