Motorola ts907 low hv

[Yamamaya42]

Originally Posted by timmy

Well I have worked on watches very tedious work so if I have to I would attempt it and the unit on eBay how is that hooked up.

I have one just like it, except mine has the AC option, that is battery only, (2 9-volts ), it simply acts as a substitute for the tuner you are testing, you unplug the RCA type cable from the tuner in the TV and plug it into the sub tuner, then feed the RF into it, set to whatever channel, adjust tuning and gain, see what happens, it's easy to use.

[timmy]

Yes I seen it I’ll get it and this chassis has an rca type plug from the tuner that plugs directly into the chassis right at the first IF and that subber looks like it has rca on the back.

[Yamamaya42]

Originally Posted by timmy

Yes I seen it I’ll get it and this chassis has an rca type plug from the tuner that plugs directly into the chassis right at the first IF and that subber looks like it has rca on the back.

Yes, that type of “RCA” IF connection is universal on most sets of the era, not sure when it became a standard.

[timmy]

Ok I had enough of this set I bought that subber hope it works so I’ll know if the tuner is bad or the IF is bad.

[Electronic M]

Originally Posted by Yamamaya42

Yes, that type of “RCA” IF connection is universal on most sets of the era, not sure when it became a standard.

On TV IFs I think it started to become common in the mid-late 50s. It never was standard on TV tuners. Many brands simply had a couple of solder stakes to solder the coax to the tuner and that was a common cost saving measure up until the combined tuner/IF systems of the solid state era.

The RCA jack as a standard connector for consumer coax applications (primarily audio) dates back to pre-WWII IIRC.

[Yamamaya42]

And if it turns out that your IF section is hopelessly borked / misaligned, you always have the option of bypassing it all and going direct A/V input, this of course would require making a small 2 transistor simple video amp to boost the standard 1v video level to the 5v that this TV expects at the 1st video amp tube grid, otherwise things will look washed out, and sound can be easily added in on the volume control plug.

[timmy]

That tuner subber don’t have a fine tune is it crystal controlled so that channel 3 is 3 aside from having the gain control. Or I could have a power supply to power the subber and leave that in circuit but I would rather keep it original if I can.

[jr_tech]

Originally Posted by timmy

Back to the same thing before sound is scratchy distorted and the -45 is jumping all over -39 -41 -30 and so on I can help but think maybe this new flyback is bad oh and no video.

What does the 190 volt supply measure when the set is “working” ? Is it still somewhat low?

jr

[timmy]

The 190v problem is solved had a bad resistor

[jr_tech]

Originally Posted by timmy

The 190v problem is solved had a bad resistor

So it is now putting out 190 volts?
Which resistor was bad?

jr

[Yamamaya42]

Originally Posted by jr_tech

So it is now putting out 190 volts?
Which resistor was bad?

jr

R93 had changed value to 800 ohms, from 560k, believe it or not

[timmy]

There seems to be a lot of believe it or nots with this set.

[timmy]

It’s almost as if the 6hq5 rf amp tube in the tuner is bad or extremely weak I have a sub I’m Going to try.

[Yamamaya42]

Originally Posted by timmy

That tuner subber don’t have a fine tune is it crystal controlled so that channel 3 is 3 aside from having the gain control. Or I could have a power supply to power the subber and leave that in circuit but I would rather keep it original if I can.

I have the 4-c version.

http://suzaku.live-evil.org/0922222215.jpg

that other one prob DOES have fine tuning, note the difference in the tuning nob, the wider control behind the one you got may be fine tuning.

[timmy]

Well I hope it works after all it’s from around 1974 I don’t want to have to fix it to get it to work lol.