Connecting to a monitor

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OldCoder
Posts: 5
Joined: 25 Jul 2014 20:59

Connecting to a monitor

Post by OldCoder » 26 Jul 2014 08:51

I'd be interested in to hear how others are setting up their MTX's.

I tried to get my video out on to my TV using the RF out initially. I have two modern TV's and only one of them would allow me to tune in the Memotech's video and even then I needed to fine tune quite a lot to get a stable picture, the other TV skips over the signal, which doesn't seem strong enough to cause the auto tune to lock in (no manual tune option).

What I eventually did was to use a BNC to din adapter connected to the MONITOR output on the MTX plugged into a din to din lead which I then plugged into composite input on the back of my LG TV and got a really good solid picture. For sound I just took the HiFi output out to a mixer I have on my desk through to an amp.

I guess most people here will use the Rememotech for video output?

As TV's are becoming all digital I suppose connecting up to a TV aerial input will become impossible.
MTX512: Serial Number: 512/15489 64k Memory

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Dave
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Re: Connecting to a monitor

Post by Dave » 26 Jul 2014 09:41

Hi Keith,

As you have seen, the RF modulator (TV) output can be pretty flakey. My original MTX drifts a bit, if I tune the TV to channel 36 and tweak it with the "fine tuning" option that my TV has, then it's ok for a while. As the machine warms up, it drifts off station though so I have to retune.

As you have seen, the composite video output is much more reliable,
I just use a BNC to phone connector and another phono for the audio and feed them both to the TV.

Let me just clarify the REMEMO........ options

REMEMOTECH is Andy's complete MTX hardware emulation in an FPGA, the normal MTX video (40 column) output as well as the emulated 80 column screen use the DE1 VGA output, you switch between them as required.

REMEMORIZER is the add on for the MTX that emulates the FDX or SDX disk systems (as well as having additional functionality). Like those legacy CP/M system, REMEMOrizer needs two outputs, one for the MTX video output for the 40 column screen and one for the VGA output from the 80 column card emulation. No VGA output from the MTX video, or not easily anyway

Regards
Dave

OldCoder
Posts: 5
Joined: 25 Jul 2014 20:59

Re: Connecting to a monitor

Post by OldCoder » 26 Jul 2014 10:17

Thanks Dave, my bad, I used the term 'din' when I meant 'phono'

What you described regarding the RF output is spot on for the TV that I can get to tune in, although the picture settles down after 10 minutes once everything is fully up to temperature. After discovering I could use the phono option the TV option has become redundant anyway :)

Loving looking at the old games. So many good memories are being bought back, but I'm shocked just how hard you have to work at the keyboard, when compared to modern ones. It's a great workout for the fingers :o but to think of the hundreds of hours I used to sit at my machine thinking it was to best you could ever experience :P
MTX512: Serial Number: 512/15489 64k Memory

Martin A
Posts: 417
Joined: 09 Nov 2013 21:03

Re: Connecting to a monitor

Post by Martin A » 26 Jul 2014 10:29

I use a BNC to Phono cable I've had since the 80's for the composite video, and phono to phono for the audio, to connect the MTX to a flat screen Sony TV. You can see it in a few of the Magrom development pictures on Dave's site the picture is pretty good.

That particular model also has colour difference inputs as well as composite, but when I connected the VDP output directly to them there was way too blue tint. So I stick with the composite.

A cheap 19" widescreen monitor seems happy to talk to the VGA output from the rememorizor, but the Sony won't lock on. So I cant switch between the 40 and 80 column on the same screen.

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