[EICO] Eico 723 Low Grid Drive

Mon, 10 Mar 2003 08:42:58 -0500

Hi Carl,
and also list members, I have an Eico 723 I also use the 722 VFO with it.
As for the chirp, sounds like the 6CL6 screen resistor might be changing
value, and or, the filter caps/voltage divider network is not working, could
be dried out electrolytics. I would definitely check the voltage at the
screen
of the 6CL6. Do you have the manual, if not it is available at the B.A.M.A.
site under Eico. As for the low 15 meter drive I think you should check the
15 meter grid input coil to the 6DQ6, make sure it isn't distorted or burned
open. Of prime consideration is the power supply components.

If I can be of assistance just ask.
http://eshop1.chem.buffalo.edu
73
Jim
WB2FCN

----- Original Message -----
From: "Carl Strode" <[email protected]>
To: <[email protected]>
Sent: Sunday, March 09, 2003 5:44 PM
Subject: [EICO] Eico 723 Low Grid Drive

> My Eico 723 has low grid drive only on 15 meters.
> Plenty of drive on 80, 40, 20 and 10.
>
> On 15, the max drive is only about 1.5 ma.
>
> If I hook up the 722 VFO, the drive is even less.
>
> I have not checked the 722 VFO yet, but since with any xtal, and even
> with the VFO the 15-meter grid drive is low, I am leaping to the
> conclusion that the 723 has a problem.
> The part that bugs me is that the drive on 10 seems to be great, only
> low on 15.
>
> I have not operated a 723 for over 25 years, and cannot recall how my
> original novice rig behaved.  I don't think I ever even saw a manual
> until recently.
>
> The 723 I now have puts out from 30 to 40 watts depending upon the band
> which seems to be about right for the rated input.
>
> Of course it chirps, with the chirp getting progressively worse from 80
> to 10.  15 seems to be the worst.
>
> Any suggestions?
> Please help.
>
> Also, when trying to neutralize the rig in accordance with the manual,
> adjustment of the neutralizing capacitor does not seem to have much, if
> any impact.  When watching the grid drive level on 20 meters and then
> adjusting the plate tuning, on the very slightest movement of the meter
> is noted, regardless of where the cap is set.  I have set it as best I
> can to a place that has the smallest of twitches, as opposed to a
> slightly larger "twitch".
>
> Carl WA7CS
> Pasco, WA
>
> [email protected]
>
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