Hi again, Larry--
I just dug through my Omni folder and found a Ten-Tec modification for the
Omni meter lamp.
The modification sheet came with two parts, a 1892 bayonet base bulb (14.4
volt - 0.12 amp) and a 10 ohm, 1/2 watt resistor.
Here are the modification steps:
1. Remove CM47 Bulb.
2. Cut out resistor on base of bulb.
3. Install new bulb (1892).
4. Install 10 ohm resistor as shown. (Diagram shows the new resistor
connecting from the red wire on the Mic/Blanker pot down to the lug on the
lamp.) In the circuitry, the lamp and the resistor wind up being in series
and across the 12 volt line. This is where I used the 33 ohm resistor
instead of the 10 ohm that Ten-Tec supplied, and I've never lost a lamp
since!
I'm sending a copy of this to the Ten-Tec reflector in hopes that it helps
someone.
73, Mike N4NT
----- Original Message -----
From: "Mike Hyder -N4NT-" <N4NT@chartertn.net>
To: "Larry Belcher" <k4cl@arrl.net>
Sent: Saturday, June 01, 2002 9:13 PM
Subject: Re: Ten-Tec Omni-D S-Meter Bulb
> Hi, Larry--
>
> The type 47 lamp in the Omni's meter lighting has a 180 ohm resistor in
> series with it in the schematic of the rig. What I did was to put a 33
ohm,
> 1 watt resistor in series with the bulb, right at the bulb. The 1 watt
may
> have been overkill but that's what I had on hand. A 27 ohm resistor would
> work about as well. I tried a 100 ohm resistor but it made the bulb
really
> dim.
>
> Just above the dial skirt is a pointer that is illuminated with a 'grain
of
> wheat' bulb. Changing that bulb requires removing the front panel and
then
> removing the escutcheon from it. Because this is such a bother, I put a
100
> ohm resistor in series with that bulb. For this bulb, the 100 resistor
> works just fine. The resistor for that one MUST be installed behind the
> escutcheon, as I recall, because the 12V that is supplied to the front
panel
> is also needed for the two LED's. That is not something I'd do unless I
had
> to be in there for some other reason (like rebuilding the PTO). Be
advised
> that there is a 3-pin plug that is used to connect the front panel to the
> chassis of the radio, so take the panel off gingerly.
>
> Hope this helps. Please let me know your results.
>
> 73, Mike N4NT
>
> ----- Original Message -----
> From: "Larry Belcher" <k4cl@arrl.net>
> To: <n4nt@chartertn.net>
> Sent: Saturday, June 01, 2002 8:02 PM
> Subject: Ten-Tec Omni-D S-Meter Bulb
>
>
> > Hi Mike,
> >
> > Hope this finds you and yours doing well and enjoying the hot and dry
> > weather. I need to rack your brain for a minute. I seem to remember a
> > couple of messages about the S-meter bulb for the Omni-D on the Ten-Tec
> > reflector but I have searched the archives to no avail. You might have
> > written one of them and if not you might remember or have knowledge of
> what
> > I am looking for. Manual calls for a standard 6 volt No. 47 but that is
> > pretty bright plus I seem to loose them pretty regular. Was there a
mod,
> > resistor change, or something that I seem to remember?
> >
> > Any ideas greatly appreciated Mike.
> >
> > 73,
> >
> > Larry, K4CL
>
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