19 May
2024
19 May
'24
11:59 a.m.
I have a couple of 70s/80s "home" computers (e.g. Radio Shack Color Computer)
that are intended to connect to a TV set. They don't have easily available composite
video, even internally, only modulated RF output. Currently I have an old CRT TV that I
use with them, but for various reasons that isn't practical long-term.
Does anyone know of a small TV tuner that tunes old analog TV channels (US NTSC) and
outputs composite or VGA or HDMI signals? I've looked around a bit but haven't
found anything. It's relatively easy to build one, but I would prefer a pre-built
solution. And I'm sure others have run into this same problem.
Thanks,
Will
19 May
19 May
1:31 p.m.
I presume the "digitial tv converter boxes" will pass through an analog signal,
and suspect at least some of them provide a composite output.
<pre>--Carey</pre>
On 05/19/2024 6:59 AM CDT Will Cooke via cctalk
<cctalk(a)classiccmp.org> wrote:
I have a couple of 70s/80s "home" computers (e.g. Radio Shack Color Computer)
that are intended to connect to a TV set. They don't have easily available composite
video, even internally, only modulated RF output. Currently I have an old CRT TV that I
use with them, but for various reasons that isn't practical long-term.
Does anyone know of a small TV tuner that tunes old analog TV channels (US NTSC) and
outputs composite or VGA or HDMI signals? I've looked around a bit but haven't
found anything. It's relatively easy to build one, but I would prefer a pre-built
solution. And I'm sure others have run into this same problem.
Thanks,
Will
1:59 p.m.
My personal experience with DTV boxes (and I do have a small assortment I use routinely),
is that the analog pass-through only functions with the box off (RF in->RF out), so no
chance of A/V extraction in that case. The majority of newer boxes have eliminated the
pass-through option entirely.
While not ideal if the goal is to reduce size, an old VCR is certainly smaller than a CRT
TV and could provide this functionality. While prices are now climbing on these, it should
be easy enough to obtain one with a non-functional transport for almost nothing. A handful
of the DVD/VHS combo units even had HDMI output.
Do keep in mind that some of the early home systems bend the rules with NTSC timing, so
what looks good on your CRT may not be acceptable on an LCD, and buyer-beware on the
published specs of off the shelf converters. -C
On May 19, 2024, at 8:31 AM, CAREY SCHUG via cctalk
<cctalk(a)classiccmp.org> wrote:
I presume the "digitial tv converter boxes" will pass through an analog signal,
and suspect at least some of them provide a composite output.
<pre>--Carey</pre>
> On 05/19/2024 6:59 AM CDT Will Cooke via cctalk <cctalk(a)classiccmp.org> wrote:
>
>
> I have a couple of 70s/80s "home" computers (e.g. Radio Shack Color
Computer) that are intended to connect to a TV set. They don't have easily available
composite video, even internally, only modulated RF output. Currently I have an old CRT TV
that I use with them, but for various reasons that isn't practical long-term.
>
> Does anyone know of a small TV tuner that tunes old analog TV channels (US NTSC) and
outputs composite or VGA or HDMI signals? I've looked around a bit but haven't
found anything. It's relatively easy to build one, but I would prefer a pre-built
solution. And I'm sure others have run into this same problem.
>
> Thanks,
> Will
1:50 p.m.
On Sun, May 19, 2024, 08:08 Will Cooke via cctalk <cctalk(a)classiccmp.org
wrote:
I have a couple of 70s/80s "home" computers
(e.g. Radio Shack Color
Computer) that are intended to connect to a TV set. They don't have easily
available composite video, even internally, only modulated RF output.
Currently I have an old CRT TV that I use with them, but for various
reasons that isn't practical long-term.
Does anyone know of a small TV tuner that tunes old analog TV channels (US
NTSC) and outputs composite or VGA or HDMI signals? I've looked around a
bit but haven't found anything. It's relatively easy to build one, but I
would prefer a pre-built solution. And I'm sure others have run into this
same problem.
I just googled "rf to HDMI" and there appear to be several options from the
usual large sellers. As I have no experience with them, I don't want to
endorse any particular model. My assumption is that they would take output
on NTSC channel 3 or 4, as was common for equipment of the time.
-Henry
1:56 p.m.
On 05/19/2024 8:50 AM CDT Henry Bent via cctalk
<cctalk(a)classiccmp.org> wrote:
On Sun, May 19, 2024, 08:08 Will Cooke via cctalk <cctalk(a)classiccmp.org>
wrote:
Perfect! Thanks. I Googled all sorts of things except "rf".
Will
I have a couple of 70s/80s "home"
computers (e.g. Radio Shack Color
Computer) that are intended to connect to a TV set. They don't have easily
available composite video, even internally, only modulated RF output.
Currently I have an old CRT TV that I use with them, but for various
reasons that isn't practical long-term.
Does anyone know of a small TV tuner that tunes old analog TV channels (US
NTSC) and outputs composite or VGA or HDMI signals? I've looked around a
bit but haven't found anything. It's relatively easy to build one, but I
would prefer a pre-built solution. And I'm sure others have run into this
same problem.
I just googled "rf to HDMI" and there appear to be several options from the
usual large sellers. As I have no experience with them, I don't want to
endorse any particular model. My assumption is that they would take output
on NTSC channel 3 or 4, as was common for equipment of the time.
-Henry
> 
1:53 p.m.
On Sun, May 19, 2024 at 06:59:50AM -0500, Will Cooke via cctalk wrote:
I have a couple of 70s/80s "home" computers
(e.g. Radio Shack Color Computer) that are intended to connect to a TV set. They don't
have easily available composite video, even internally, only modulated RF output.
Currently I have an old CRT TV that I use with them, but for various reasons that
isn't practical long-term.
Does anyone know of a small TV tuner that tunes old analog TV channels (US NTSC) and
outputs composite or VGA or HDMI signals? I've looked around a bit but haven't
found anything. It's relatively easy to build one, but I would prefer a pre-built
solution. And I'm sure others have run into this same problem.
Nothing small. I've had tuner boxes in the past that were as large as
a VCR. I also have used a VCR to do the function you are asking about.
Surely an ancient used VCR would be the absolute cheapest solution.
NTSC Tuner boxes are a niche item, and exist, but are _expensive_.
The same with video demodulators, they exist, but are very pricey.
The retro-home computer community has come through alot with hardware to get something
more modern for video output on these old computers.
Ie. https://coco3.org/ mentions several FPGA projects to plug into the computer to
get modern video out.
I'm eyeing a https://www.reactivemicro.com/product/a2fpga-multicard/ for my Apple ][
The main problem with the hobiest hardware, is that they only do small
batches, and have to get enough orders together to make it worthwhile
to do another run. So you may have to wait a very long time. Sometimes you can
find these used on eBay (for outrageous prices, but such is the nature).
But as you've seen, alot of these are open-hardware, so people can do
it themselves with enough traction behind it. Print-to-order PCBs are super cheap.
Electronics parts can be expensive, but thats what makes these small hobbiest boards
expensive, that they don't get to order the big chips in batches of 10,000 to get a
good price.
6:57 p.m.
On Sun, 19 May 2024, Will Cooke via cctalk wrote:
I have a couple of 70s/80s "home" computers
(e.g. Radio Shack Color
Computer) that are intended to connect to a TV set. They don't have
easily available composite video, even internally, only modulated RF
output. Currently I have an old CRT TV that I use with them, but for
various reasons that isn't practical long-term.
Does anyone know of a small TV tuner that tunes old analog TV channels
(US NTSC) and outputs composite or VGA or HDMI signals? I've looked
around a bit but haven't found anything. It's relatively easy to build
one, but I would prefer a pre-built solution. And I'm sure others have
run into this same problem.
VCR,
Digital converter box,
Closed caption decoder
even some TVs have a composite out, all of which had RF input
All of those are now old.
Not all of those have composite output out, but such do exist for each of
those.
You should know that your specific example, Radio Shack Color Computer,
can produce composite internally with trivial modifications.
A large number of such machines internally share a common RF module; if
you identify the input to their RF modulator, often clipping onto that may
be all you need.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
20 May
20 May
8:50 a.m.
On Sun, May 19, 2024 at 1:08 PM Will Cooke via cctalk
<cctalk(a)classiccmp.org> wrote:
Does anyone know of a small TV tuner that tunes old
analog TV channels (US NTSC) and outputs composite or VGA or HDMI signals? I've looked
around a bit but haven't found anything. It's relatively easy to build one, but I
would prefer a pre-built solution. And I'm sure others have run into this same
problem.
Not for NTSC video, but for the UK UHF analogue TV...
About 30 years ago we had a hobbyist electronics shop chain called
Maplin, who produced and sold their own range of kits, many of them
very good. When NICAM stereo TV sound was introduced in the UK, they
produced a kit to decode the NICAM signal to audio. In fact it was a
total of 3 kits -- the NICAM decoder board, a TV tuner/IF strip to
feed it (if you didn't want to try to tap off the NICAM subcarrier
from your existing TV 's tuner), and the case/connectors/tuner channel
memory/etc..
I built the entire system for my parents who had a VCR [1] that could
record stereo sound from line-level inputs but which pre-dated NICAM.
I then realised that the tuner/IF board on its own, with a multi-turn
pot added for tuning (rather than the remote control/memory control IC
used in the full unit) would be ideal for turning the RF output of UK
home computers into composite video. So I built a second tuner board
for that. Still have it, still use it.
-tony
10:13 a.m.
At one time I had a few Bt848 based PCI TV tuner cards for a PC - Hauppage
was a big player but there were others. Some were composite video in, some
also had a TV tuner section.
I tried one as a video converter for PAL composite out from some home micro
- possibly a Jupiter Ace. It wasn't that great, to be honest and doubtless
the RF input is even worse but you don't really expect a great deal from an
RF output in terms of video quality. If you can find one (most have been
replaced by DVB-T cards : do they also accept analogue TV signals ?) they
should be almost free.
On Mon, May 20, 2024 at 10:03 AM Tony Duell via cctalk <
cctalk(a)classiccmp.org> wrote:
On Sun, May 19, 2024 at 1:08 PM Will Cooke via
cctalk
<cctalk(a)classiccmp.org> wrote:
Does anyone know of a small TV tuner that tunes
old analog TV channels
(US NTSC) and outputs composite or VGA or HDMI signals? I've looked around
a bit but haven't found anything. It's relatively easy to build one, but I
would prefer a pre-built solution. And I'm sure others have run into this
same problem.
Not for NTSC video, but for the UK UHF analogue TV...
About 30 years ago we had a hobbyist electronics shop chain called
Maplin, who produced and sold their own range of kits, many of them
very good. When NICAM stereo TV sound was introduced in the UK, they
produced a kit to decode the NICAM signal to audio. In fact it was a
total of 3 kits -- the NICAM decoder board, a TV tuner/IF strip to
feed it (if you didn't want to try to tap off the NICAM subcarrier
from your existing TV 's tuner), and the case/connectors/tuner channel
memory/etc..
I built the entire system for my parents who had a VCR [1] that could
record stereo sound from line-level inputs but which pre-dated NICAM.
I then realised that the tuner/IF board on its own, with a multi-turn
pot added for tuning (rather than the remote control/memory control IC
used in the full unit) would be ideal for turning the RF output of UK
home computers into composite video. So I built a second tuner board
for that. Still have it, still use it.
-tony
10:22 a.m.
I've also had TVs with modular RF inputs. One was a huge plasma wall TV and
the other a tiny cheap caravan TV but both had locations for an RF input
card which I assumed could be replaced by cards to suit local national TV
standards. These have no visible controls and, like the PC TV cards,
probably have an I2C tuner module. The linux TV application xawtv has code
for controlling these.
A similar device was used with BBC and Archimedes computers to receive the
UK teletext service - it tuned to the TV services and extracted data that
was broadcast in the vertical blanking interval.
On Mon, May 20, 2024 at 11:13 AM Adrian Godwin <artgodwin(a)gmail.com> wrote:
At one time I had a few Bt848 based PCI TV tuner cards
for a PC - Hauppage
was a big player but there were others. Some were composite video in, some
also had a TV tuner section.
I tried one as a video converter for PAL composite out from some home
micro - possibly a Jupiter Ace. It wasn't that great, to be honest and
doubtless the RF input is even worse but you don't really expect a great
deal from an RF output in terms of video quality. If you can find one (most
have been replaced by DVB-T cards : do they also accept analogue TV signals
?) they should be almost free.
On Mon, May 20, 2024 at 10:03 AM Tony Duell via cctalk <
cctalk(a)classiccmp.org> wrote:
On Sun, May 19, 2024 at 1:08 PM Will Cooke via
cctalk
<cctalk(a)classiccmp.org> wrote:
Does anyone know of a small TV tuner that tunes
old analog TV channels
(US NTSC) and outputs composite or VGA or HDMI signals? I've looked around
a bit but haven't found anything. It's relatively easy to build one, but I
would prefer a pre-built solution. And I'm sure others have run into this
same problem.
Not for NTSC video, but for the UK UHF analogue TV...
About 30 years ago we had a hobbyist electronics shop chain called
Maplin, who produced and sold their own range of kits, many of them
very good. When NICAM stereo TV sound was introduced in the UK, they
produced a kit to decode the NICAM signal to audio. In fact it was a
total of 3 kits -- the NICAM decoder board, a TV tuner/IF strip to
feed it (if you didn't want to try to tap off the NICAM subcarrier
from your existing TV 's tuner), and the case/connectors/tuner channel
memory/etc..
I built the entire system for my parents who had a VCR [1] that could
record stereo sound from line-level inputs but which pre-dated NICAM.
I then realised that the tuner/IF board on its own, with a multi-turn
pot added for tuning (rather than the remote control/memory control IC
used in the full unit) would be ideal for turning the RF output of UK
home computers into composite video. So I built a second tuner board
for that. Still have it, still use it.
-tony
187
days inactive
188
days old
9 comments
8 participants
participants (8)
-
Adrian Godwin -
CAREY SCHUG -
Cory Heisterkamp -
Doug McIntyre -
Fred Cisin -
Henry Bent -
Tony Duell -
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