View Full Version : Which Digital converter box is the good one?


Eric H
06-20-2013, 12:54 PM
I picked up a Channel Master last weekend, it looks like a quality unit and it has Composite output so I hope it's well built.

I think it's this one:
http://0.tqn.com/d/tv/1/0/P/3/Channel-Master-CM-7000.jpg

Zenith26kc20
06-20-2013, 02:05 PM
That is a good one. The other good ones are DigitalStream and the Insignia/Zenith, both which are LG. The Channel Master is the only good one with S out.

radiotvnut
06-20-2013, 04:51 PM
I own a channel master and two digitalstream boxes and they are good performers and have never given me any problems. I also have a Funai/Magnavox box that someone gave me and it's on the kitchen TV. I've never had a problem with it; but, it does not appear to be as sensitive as the other boxes and the maggie box has no buttons on it; so, you're screwed if you lose the remote or if the remote fails.

Don't waste your money on the Apex boxes. The first one of those that I owned came from my neighbor after he went into a nursing home. He'd only had it about a month when I got it and after about 4 hours of me using it, the thing crapped out. The symptom looked like bad power supply filter capacitors; but, I couldn't find any bad caps. Later, someone I know who sells stuff got the same type Apex box in with a bunch of junk; but, it didn't have the remote and he gave it to me. I had saved the remote from my neighbor's old box; but, this box had the exact same problem as the first one. When the first one I had worked, the performance was crappy and it got hot enough on top to fry an egg.

davet753
06-21-2013, 08:54 AM
There's 3 electrolytic capacitors in the Apex boxes that go bad. I can't remember the values of them, but I have fixed several of those for friends by replacing the caps with ones of a higher voltage rating.

I appreciate the info on the channel master and digitalstream boxes. I have over-the-air reception at my camper and use a Magnavox box. I have never been happy with the reception at all. I think I should try to find a better converter box.

DERI
06-21-2013, 08:57 AM
The Channel Master will need a recap (red lite of death) . . . There are 6 capacitors involved. Use double rated voltage and they'll last. I've fixed about 6 of these and they are worth it.

wa2ise
06-21-2013, 09:32 AM
I've modified my Channel Master to produce TV signals without the chroma subcarrier, to feed my early 1950's B&W TV sets. Back then, they displayed the full resolution of the 4.2MHz luma signal, as NTSC color had not come out yet. Later B&W sets usually low pass filtered the luma to get rid of the color subcarrier.

http://www.videokarma.org/attachment.php?attachmentid=167111&d=1273091337

There is a chip in this box that sums the S video signals together to produce the composite video fed to its modulator. Here I insert a switch to pass or stop the chroma from getting to the sum circuit.