Amps
[Top] [All Lists]

[Amps] Alpha 87a

To: <amps@contesting.com>
Subject: [Amps] Alpha 87a
From: "JOS Earthlink" <jsternmd@earthlink.net>
Date: Sun, 31 Dec 2006 16:35:16 -0500
List-post: <mailto:amps@contesting.com>
Hi All,

I just got an ETO Alpha 87a with Alphamax and it seems to work very nicely.
I only see one problem with the amp - I'm almost certain that the RF input
coils for  many of the bands need to be adjusted.  I noticed that the SWR
out of the TS-950SD was running high into the 87a on a few bands.  To be
absolutely certain I placed my Powermaster powermeter between the TS-950SD
and the 87a.  I think the 87a RF input circuits are out of whack:

At 28.0000 - 29.7000 Mhz SWR into the 87a is from 1.5 - 2.0
At 21.0000 - 21.4500 Mhz SW goes from 2.3 - 1.8
At 18.068 - 18.168 Mhz SWR goes from 1.7 - 1.4
At 3.5000 - 4.000 Mhz SWR starts at 1.3 but goes 2.2 above 3.700 Mhz.

I tried this with other tranceivers instead of the TS-950SD and all show the
same.  On my Collins 30L-1 it's a piece of cake to adjust the RF coil for
each band by looking at Reflected power between the exciter and amp tuning
the RF coil for minimal Reflected power but the 87a is a new beast for me
plus I don't have any schematics.  Any advice appreciated.

Have a Happy and Healthy New year to All !

73 Jerry
K1JOS
CCA #11906

_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>