FT-1000 Headphone Audio

Tue May 17 14:22:13 EDT 1994

W0UN writes:

>The FT-1000 seems to drive the Yaesu headphones adequately, but not the
>Heil and I think it is a function of both headphone impedance and
>efficiency.

I measured the impedance (DC resistance) of the stock headphone elements
in the Pro Set and found them to be about 390 ohms. I requested a new pair, 
as the audio for this ole deaf rocker was a bit low.  Heil happily sent me 
the 16 ohm units, gratis. Thats what I call custromer service! They were 
retrofitting the phones being returned at that time (last month) with the 
16 ohm units.  The sweet gal on the telephone told me that they were ordering 
1000, 8 ohm units and they were due in soon. I measured the impedance of the 
new elements & found them to be around 32 ohms I guess they achieve 16 ohms 
when the phone elements are driven in parallel, as is the case with most rigs. 
I believe the FT-1000 uses a stereo amp, hence each channel looks into 32 ohms. 
Anyway, the audio from the 765 is now Okay, not ear splitting, but since the 
pads tend to cancel the noise in the shack its ample.

Since the mike element is designed to be close talked, a neat addition to 
headset would be a wind-screen.  A friend who attended Dayton this year, 
asked Mr. Heil if such an animal existed and was he told it does not.  
I got rid of the pop-poping by fashioning a wind screen from some foam 
packing material. Now, I have one heck of a headset!

73 de Walt - K2WK - waltk at pica.army.mil

>From gt5830b at prism.gatech.edu (KUNKEE,DAVID BRYAN)  Wed May 18 14:52:35 1994
From: gt5830b at prism.gatech.edu (KUNKEE,DAVID BRYAN) (KUNKEE,DAVID BRYAN)
Date: Wed, 18 May 1994 09:52:35 -0400 (EDT)
Subject: June VHF SKED request
Message-ID: <199405181352.JAA04112 at acme.gatech.edu>

Hi everyone,
I am looking for SKEDS during the June VHF contest as well.
The 4-landers will be operating from Franklin mountain (NC) EM-85
and using the call W4NT.  We will have 6 through 432 MHz  (big
stations for 6 and 2). 

73 de Dave, K0DI
gt5830b at prism.gatech.edu

>From sellington" <sellington at mail.ssec.wisc.edu  Tue May 17 14:44:42 1994
From: sellington" <sellington at mail.ssec.wisc.edu (sellington)
Date: 17 May 94 13:44:42 U
Subject: FT-1000 and Heil headphones

There's something strange here.  Typical headphones only require a few
mW to achieve ear-splitting levels.  Either the Heil headphones are very,
very inefficient (even compared to high fidelity headphones), or their
impedance is so high that the Yaesu drive can't supply enough voltage.

Scott   K9MA

>From Sig <0006481603 at mcimail.com>  Wed May 18 03:24:00 1994
From: Sig <0006481603 at mcimail.com> (Sig)
Date: Tue, 17 May 94 21:24 EST
Subject: Metric SS Hardware
Message-ID: <75940518022457/0006481603PK3EM at mcimail.com>

I have an EMOTO 1300MSAX which uses all metric hardware.  I want to double-
nut some of the bolts holding the jaws of the rotor, but have not been able
to locate a supplier of Stainless Steel hardware in metric sizes.  In partic-
ular, I need 10mm nuts.  Does anyone know of a source for these?  

Also would like to know if anyone knows the pitch of the threads of the bolts
used on the mast clamp?  The skimpy manual that comes with this rotor does not
give any indication of the pitch of any of the hardware used.  The bolts in
question are 10mm X 100mm.

Thanks! de Sig, N3RS
6481603 at MCIMail.com