[Icom] re pa output trans in Icom transceivers

Wed, 18 Sep 2002 00:17:01 -0700

Hi Jim,

It may be a regulator problem. The technician at the Icom Canada service
centre informed me today that the IC-746 has separate HF/6m and 2m PA
sections - as illustrated in the IC-746 product brochure.
http://www.qsl.net/kb9sss/IC-746/IC-746-Brochure.pdf

Cheers for now, 73,
Adam VA7OJ/AB4OJ

-----Original Message-----
From: [email protected] [mailto:[email protected]]On
Behalf Of Jimmie Sowell
Sent: Tuesday, September 17, 2002 22:57
To: [email protected]
Subject: Re: [Icom] re pa output trans in Icom transceivers

If this is true

"> In the IC-746, there are separate PA's for HF/6m and 2m. Each PA uses a
> matched pair of 2SC2694's. The drivers are matched pairs of 2SC1972's, and
> the pre-drivers are 2SC1971's (separate HF/6m and 2m chains)."

then why did my HF/6 and 2 meters all go out at the same time?  Could I have
a problem other than the PA's?  Anybody have other ideas before I send it
off to ICOM.

73, Jim

----- Original Message -----
From: "Adam Farson" <[email protected]>
To: <[email protected]>
Sent: Tuesday, September 17, 2002 11:32 AM
Subject: RE: [Icom] re pa output trans in Icom transceivers

> Hi Fern,
>
> The PA transistors in the IC-756 are a matched pair of 2SC2694's. The
> drivers are a matched pair of 2SC1972's, and the pre-driver is a 2SC1971.
>
> In the IC-746, there are separate PA's for HF/6m and 2m. Each PA uses a
> matched pair of 2SC2694's. The drivers are matched pairs of 2SC1972's, and
> the pre-drivers are 2SC1971's (separate HF/6m and 2m chains).
>
> Replacement devices are available form Icom or from RF Parts
> http://www.rfparts.com/
>
> I would not recommend that you attempt replacement unless you have access
to
> a service manual, the requisite test equipment as specified in the service
> manual, and appropriate soldering/desoldering equipment.
>
> Best 73,
> Adam, VA7OJ/AB4OJ
> North Vancouver, BC, Canada
> http://www.qsl.net/ab4oj/
> Note new e-mail address:
> mailto:[email protected]
>
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]]On
> Behalf Of Fern Rivard
> Sent: Tuesday, September 17, 2002 08:40
> To: [email protected]
> Subject: [Icom] re pa output trans in Icom transceivers
>
>
> Could someone please advise me as to what pa output transistors are used
in
> the IC-746 and the IC-756 transceivers and also wonder if Icom uses a
> matched pair or no?  Best of 73's from Fern
>
>
> ----
> Your Moderator: Dick Flanagan W6OLD, [email protected]
> Icom FAQ: http://www.qsl.net/icom/
>

----
Your Moderator: Dick Flanagan W6OLD, [email protected]
Icom FAQ: http://www.qsl.net/icom/