Riddled TV Repair Forum
Service Menu and Manual Schematics
 
   
 FAQFAQ   SearchSearch   RegisterRegister 
   Log inLog in 
NEC C9-200   Goto page 1, 2  Next  
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair
 
Author Message
llou



Joined: 17 Mar 2008
Posts: 5
Location: Canada

PostPosted: Mon Mar 17, 2008 8:45 am    Post subject: NEC C9-200 Reply with quote

Hi; I am newbie and have no experience with modifying TVs. I was given an old hospital color TV “NEC C9-200” (DC 12-24 v, 27 Watts). It has no power cord only RG59 cable plug.
Does anybody know anything about this TV and how to convert it to normal use? What kind of power supply box do I need? And how to hook it up to an antenna?

Images for this TV here:









Your help would be appreciated
Google

PostPost subject: Advertisement

kuhurdler



Joined: 28 Dec 2006
Posts: 2879
Location: Overland Park, KS

PostPosted: Mon Mar 17, 2008 9:27 am    Post subject: Reply with quote

It looks like there is a power jack on the right side.
It's pretty hard to tell from your pictures though, they are pretty blurry.

Seriously though, I have never seen a TV like this, but I wouldn't spend much time on it unless you just really enjoy fixing things.
llou



Joined: 17 Mar 2008
Posts: 5
Location: Canada

PostPosted: Mon Mar 17, 2008 10:06 am    Post subject: Thanks Reply with quote

Thanks for your reply; yes I would really like to know how to modify this TV, it would be an enjoyable challenge.

There is no power jack on the right side. And I uploaded more images. I know the first set were a bit blurry.









Thanks again
kuhurdler



Joined: 28 Dec 2006
Posts: 2879
Location: Overland Park, KS

PostPosted: Mon Mar 17, 2008 10:42 am    Post subject: Reply with quote

follow the wires to those LED lights that are next to the cable jack. I'd bet they indicate power somehow.
I've seen cable amps that use DC power injected into the coax. Perhaps this uses the same scheme.
llou



Joined: 17 Mar 2008
Posts: 5
Location: Canada

PostPosted: Mon Mar 17, 2008 1:43 pm    Post subject: AC adaptor Reply with quote

There was a “+” and “–“ at the bottom of the cable jack box, so I attached a 12v AC adaptor and I got power but no picture. I think your right about the cable amp. Do you know of hand what do I need to purchase to get this TV working?
Google

PostPost subject: Advertisement

kuhurdler



Joined: 28 Dec 2006
Posts: 2879
Location: Overland Park, KS

PostPosted: Mon Mar 17, 2008 2:03 pm    Post subject: Reply with quote

I'm guessing you meant a 12V DC adapter... not AC?
llou



Joined: 17 Mar 2008
Posts: 5
Location: Canada

PostPosted: Mon Mar 17, 2008 5:10 pm    Post subject: Reply with quote

I used a Universal AC Adaptor and set at 12v.

Anyway is this TV has what they call a “BNC connection” would it work with RF modulator?

thanks
kuhurdler



Joined: 28 Dec 2006
Posts: 2879
Location: Overland Park, KS

PostPosted: Tue Mar 18, 2008 3:31 pm    Post subject: Reply with quote

alright, Im just going to assume its a 12VDC input that you gave it. I dont think its possible it could run on 12VAC if it is the same input as the tuner.

BNC is not unusual. its the same signal input as an F-connector (standard coax), so there is no reason it wouldn't work with an RF modulator, unless your TV also takes some kind of proprietary signal too.

If it were me, I would find some place to inject 12VDC and hook up some kind of antenna to the tuner. I would probably inject the power wherever those LED lights are fed from... as I suggested earlier.
THen I would probably use a paper clip and attach it to the center wire of the bnc connector. If you live near a broadcast tower, it should pick up a dirty analog signal (till feb 2009 anyway)... Be forewarned. that paperclip will now be live 12 volts...

Then again, if it really were me, i would have already tossed this TV and picked up a larger TV from the curb on trash day. They're not that uncommon. But I understand the urge to fix things.
llou



Joined: 17 Mar 2008
Posts: 5
Location: Canada

PostPosted: Wed Mar 19, 2008 7:56 am    Post subject: Thanks Reply with quote

Ok thanks for your help. The reason why I didn’t throw it out, is because I never seen this type of setup before and I was just curious.
TRENT310



Joined: 24 Mar 2009
Posts: 1

PostPosted: Tue Mar 24, 2009 1:03 am    Post subject: Reply with quote

I got the same TV a while ago and modified it for normal use, but I see this thread did not get fully answered.

Even though this thread is basically a year old - Just for the sake of the internet and anyone else who may end up searching for this model, here is some information:

If you have a way of injecting 24V and RF into the line, you may have a decent line-powered television. However, for most purposes, that's not possible.

The connector it has (at least on mine) is a G-type connector, which is also rated to carry power.

Do not use the built in power splitter. Basically you can put power in the center pin, but then you would have to carefully block power backflow into whatever RF source it is plugged into. I would skip it completely. On the other side of the splitter are 2 wires and a coaxial cable coming out of it. You can cut the coax and terminate it, and cut the power wires and wire power directly through that way.



My unit, at least, does not turn on with anything less than 24 volts. Even 20v won't cut it. The channel LED display will turn on, but the CRT will not start up. It pulls a decent amount of power so be sure your power supply can handle it - no wall warts, probably a decent switching supply would do well. (Trust me this television set has burned up many universal adapters and even fixed 24V adapters - although that was the thing that let me know I needed more voltage.) This is probably the problem mentioned here. Although really, that makes no sense since it SHOULD be able to operate on a wide voltage range because of the fact that it's expected to have some voltage drop at the end of long cable runs. Alas, it doesn't.


I've been trying to see if I can plug a baseband video signal into it, although I guess the fact that it has a tuner is a good thing, although it only goes up to 36.
This is the RF input, just terminate a normal female F connector onto one end and a RCA end on the other.


Tweak the focus control while the cover is open.


It's a good 9" set for situations that need colour and a compact size. And it has a ton of manual fine tuning controls at the back.

Yeah, taking pictures of TVs does not usually show them in the best light...
Display posts from previous:   
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair All times are GMT - 6 Hours
Goto page 1, 2  Next
Page 1 of 2

 


Disclaimer: All information provided by RiddledTV is strictly for information purposes only. Please observe all warnings displayed on your electronic
devices. This information should only be used to help diagnose work, and all service should be performed by a qualified technician.
Privacy Policy       Copyright © 2020 RiddledTV.com       Advertise on RiddedTV.com