View Full Version : Motorola setup


timmy
04-28-2022, 04:06 PM
Is there any short cuts to setting up a Motorola roundie since there is no service switch like the rcas.I did have a 23 inch Motorola but it’s been awhile I actually forgot what I did now that’s not good.

old_tv_nut
04-28-2022, 08:20 PM
Which chassis?

timmy
04-29-2022, 04:52 AM
Ts 907

old_tv_nut
04-29-2022, 11:02 AM
Get the SAMS from ETF:
http://www.earlytelevision.org/pdf/motorola_ts-907_sams_739-3.pdf

timmy
07-06-2022, 03:56 PM
I have 2 tubes 6aw8a and 8aw8a what would be the consequence of using the 8 volt in place of the 6 volt in a pinch

zeno
07-06-2022, 05:01 PM
I have 2 tubes 6aw8a and 8aw8a what would be the consequence of using the 8 volt in place of the 6 volt in a pinch

As a test in a pinch I see no reason not to. May work fine, who knows.
Warm up may be longer & a weak one probably show it sooner.

73 Zeno:smoke:
LFOD !

timmy
07-06-2022, 06:33 PM
I thought the 8 volts would draw to much from the heater string

Penthode
07-06-2022, 11:33 PM
I thought the 8 volts would draw to much from the heater string

The TV has parallel wired filaments. Filament power= voltage x current.

If the tube filament voltage rating is higher, for the the same filament power the filament current will be less. That means the 8 volt tube will provide less of a filament load not a greater load.

The downside is running the 8 volt rated filament on 6 volts will mean it will not be as hot. If the tube was weak at 8 volts, it will be worse at 6 volts.

timmy
07-11-2022, 01:39 PM
Ok I got this ts907 Motorola and both horz output tube plates are glowing red with no hv output any quick ideas.

Penthode
07-11-2022, 01:44 PM
Ok I got this ts907 Motorola and both horz output tube plates are glowing red with no hv output any quick ideas.

Likely no horizontal oscillator.

timmy
07-11-2022, 01:46 PM
Yes that’s what I thought but any ideas to hit first. Already recapped the electrolytics tubes changed or checked.

timmy
07-12-2022, 11:49 AM
Well I have horizontal now but the hv seems to be stuck at 20 kv adjustment won’t bring it up to 24kv so not sure if the loss of horizontal has to do with the hv not being able to adjust

timmy
07-12-2022, 01:20 PM
Next step change the caps at the oscillator tube. usually as I have found out the red caps are still good and reliable but they are from 65.

timmy
07-14-2022, 10:23 AM
On this ts907 the focus coil has a 100k resistor on it what would make this resistor burn. Don’t think I ever seen this.