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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: SteveSMS on January 30, 2006, 08:42:39 PM

Title: Problems connecting Amiga to TV
Post by: SteveSMS on January 30, 2006, 08:42:39 PM
Hi,


I bought this Amiga 1200, and i've got a few problems with it.
If it's connected to a monitor (we tested it with the seller), it works fine. But when it's connected to a TV, my colors are all messed up (RF) or it's just black&white(composite). The screen is also shaped weird. A friend of mine said it might have sync problems.

Pictures:
http://f3.channelwood.org/Amiga/AMIGA001.jpg <-- RF
http://f3.channelwood.org/Amiga/AMIGA003.jpg <-- Composite

Any advice would be helpfull.


Thanks!
Title: Re: Problems connecting Amiga to TV
Post by: amigagr on January 30, 2006, 08:49:16 PM
beside the rf connector there is a switch and a varible capacitor. test the switch to both positions and/or with a special plastic screwdriver turn arrund the capacitor until you clear the picture in the tv. or try to tune the tv manual with the microtuning selection of the menu if it has one
Title: Re: Problems connecting Amiga to TV
Post by: CDE_MusiX on January 30, 2006, 08:57:48 PM
The RF-modulator has 2 TV modes: PAL and NTSC. (A question: what you use?) If you use PAL you only plug the RF-cable to the TV, or if NTSC you must also buy a commutator.
Title: Re: Problems connecting Amiga to TV
Post by: SteveSMS on January 30, 2006, 08:58:55 PM
I already tried that...
The weird thing is that it has the same problem with Composite out, but it's black & white...

Thanks for replying though :)
Title: Re: Problems connecting Amiga to TV
Post by: SteveSMS on January 30, 2006, 08:59:48 PM
MusiX : I'm using PAL. :)
Title: Re: Problems connecting Amiga to TV
Post by: CDE_MusiX on January 30, 2006, 09:07:03 PM
strange... You can try with another TV. Is the same problem?
I use TV i too, and there are no problems using CH 36 and a cable (i can't say if is composite, RF, because i don't know about these things... i can only say you is a Jack-type plug (on the AMIGA) and a TV-receiver plug (for the TV))
Title: Re: Problems connecting Amiga to TV
Post by: amigagr on January 30, 2006, 09:07:07 PM
you can connect the amiga to a tv with a 23pin to scart cable too if you can find one...
Title: Re: Problems connecting Amiga to TV
Post by: SteveSMS on January 30, 2006, 09:10:16 PM
I've tried it with 3 TV's...
All the same  :-(
Title: Re: Problems connecting Amiga to TV
Post by: twizzle on January 30, 2006, 09:15:40 PM
hi
 have you tried wiggling the scart socket to see if       you get any colour fashes indicating a broken wire or loose terminal???

as i do get that problem myself now & again
Title: Re: Problems connecting Amiga to TV
Post by: SteveSMS on January 30, 2006, 09:24:56 PM
That's a problem too, the TV in my room doesn't have scart. It's a really old piece of junk... :)

Is it possible to connect an Amiga to a standard VGA monitor (as in, a PC monitor?)
Title: Re: Problems connecting Amiga to TV
Post by: amigagr on January 30, 2006, 09:25:30 PM
 SCART TO AMIGA (RGB) CABLE
 product code: CABSTV002   
    €21.85


@amigakit: this price is like a robbery in the street for this kind of stuff...
Title: Re: Problems connecting Amiga to TV
Post by: SteveSMS on January 30, 2006, 09:40:22 PM
Twizzle:

It's not bad contact, i tried wiggling with it and even tried other cables...
Title: Re: Problems connecting Amiga to TV
Post by: twizzle on January 30, 2006, 09:47:42 PM
hi
no you cant connect a pc moniter without towering your amiga ie madiater + graphics card  (expensive job)
Title: Re: Problems connecting Amiga to TV
Post by: amigagr on January 30, 2006, 09:52:02 PM
no you can, if it's an amiga 1200/4000 with just a cheap adaptor of 23pin to vga, and with a scan doubler/flicker fixer, a more expencive way, all amigas, take a look at http://europe.amigakit.com/
Title: Re: Problems connecting Amiga to TV
Post by: twizzle on January 30, 2006, 09:57:11 PM
i didnt think of the flicker fixer (doh)

if he`s tried the scart lead with 3 diff tv`s
then there might be a problem with the motherboard i would imagine???
Title: Re: Problems connecting Amiga to TV
Post by: amigagr on January 30, 2006, 10:05:50 PM
oh boy... the amiga has connected with rf and rca but yes finaly the problem maybe is from the motherboard but only the in the composite/rf part as the rgb output works ok with monitors as SteveSMS already said
Title: Re: Problems connecting Amiga to TV
Post by: SteveSMS on January 30, 2006, 10:06:24 PM
Hmm then i'll have to replace the mobo...

The guy i bought it from said he would replace the mobo (i emailed him about it:) )

But, if anyone knows a better solution or knows what it is, that would be better :)

Anyway, thanks for your help, guys... I really appreciate it.


Greets,


-Steve
Title: Re: Problems connecting Amiga to TV
Post by: CDE_MusiX on February 01, 2006, 03:05:13 PM
Try to use a RGB tv cable. (If there exists)
Title: Re: Problems connecting Amiga to TV
Post by: amigakit on February 01, 2006, 03:12:37 PM
Hi Steve,

Welcome to Amiga.org!

Here are your options to bypass the in-built modulator:

1. Replacement TV modulator (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=227) which will connect to the 23-pin RGB socket
2. Scart to RGB cable (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=226) again connect to the 23-pin RGB socket
3. Scart to AV cable (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=211) (connects to the yellow AV connector)
4. Flicker Fixer/Scandoubler (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=414) to connect to PC Monitor
5. SVGA to RGB adapter (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=183) (same as 4. but only VGA frequency modes)

Hope this helps!

EDIT: I see that option 2. is a no go as you dont have SCART and composite exhibiting the same problem.
Title: Re: Problems connecting Amiga to TV
Post by: Tomas on February 01, 2006, 05:33:28 PM
First make sure that the cable is alright, if that is the case, then you could just get one of those tv modulators that orginally comes with the a500. I am sure you can find one for cheap on a auction site or similar. The modulator converts the signal from the rgb port to both composite and rf. http://www.ntrautanen.fi/computers/commodore/images/amiga/a520.jpg (http://www.ntrautanen.fi/computers/commodore/images/amiga/a520.jpg)

For using a vga monitor you can get a flicerfixer, which will both convert the rgb into standard vga and will double the refresh rate, so that it will be compitable with most monitors. http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=414 (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=414)
Title: Re: Problems connecting Amiga to TV
Post by: Tomas on February 01, 2006, 05:36:12 PM
Quote
But, if anyone knows a better solution or knows what it is, that would be better :)

Even if that is the case, it will probably work with such a tv modulator or flicker fixer or a amiga monitor using the rgb port.

The best way would be to test it out with someone elses amiga monitor or similar.
Title: Re: Problems connecting Amiga to TV
Post by: Voicer on February 06, 2006, 02:27:58 PM
Hello,

I have same problem, same weird image on my TV. Cable is ok, and for now any other option (than using that RF modulator) isn't possible.

I figured out, that when i try to slighly move that RF up/down, for few seconds tv output fixes, so it looks like some kind of failure inside modulator?  
Title: Re: Problems connecting Amiga to TV
Post by: CLS2086 on February 06, 2006, 04:21:56 PM
It seems like a ground problem, or a capacitor dead, or a dying Power Supply Unit ...
So check that quickly, these are very commun electrical problems and can cause this on your screen.
Have you tried to unplug your floppy drive and HDD as they draw lot of power ?

I still wonder why people use RF or composite connnector nowadays. Since January 1st 1980, most new TV and 15 Khz European monitors were equipped with a Peritel/Scart/EuroConnector with RBG + "nationnal" composite entrance (PAL or SECAM), then in 1986 all new TV must had been equipped with, It also become to be used in Japan and others Asian countries, and in 1990 all have to support PAL (and also SECAM for France) color systems...
At the same time, it also arrived in Africa.

Do you live in these primitives rebel countries like the USA or Australia ?   :lol:
Title: Re: Problems connecting Amiga to TV
Post by: Voicer on February 06, 2006, 04:50:50 PM
nah :) poland, and i use tv which is older than me i guess... '70 or something like that, just because it was my first "screen" (and because i don't have any other free for now)

Anyway, i rip everything into pieces, cleaned up, etc... I didn't saw anything unusual, and when i put this stuff together again... it works, so i fix it by accident :P

Its possible that its voltage problem, because i use floppy power for 3,5 hd inside... but for now everything is ok :)
Title: Re: Problems connecting Amiga to TV
Post by: Boot_WB on February 06, 2006, 09:00:25 PM
Bizarrely, having just connected the composite out of my Voodoo3 from PC to a TV I find this gives a black and white signal also.  
I am plugging it into a composite in (AFAIK) AV socket, there is no seperate input for chroma etc.  

Weird, or is it just incompatible?
Title: Re: Problems connecting Amiga to TV
Post by: Tomas on February 06, 2006, 09:31:37 PM
Quote
I still wonder why people use RF or composite connnector nowadays. Since January 1st 1980, most new TV and 15 Khz European monitors were equipped with a Peritel/Scart/EuroConnector with RBG + "nationnal" composite entrance (PAL or SECAM), then in 1986 all new TV must had been equipped with, It also become to be used in Japan and others Asian countries, and in 1990 all have to support PAL (and also SECAM for France) color systems...

Probably because the amiga was never bundled with such a cable and the fact that you have to buy a special rgb to scart adaptor cable from a special shop selling amiga items.

I find it really weird myself that even the a1200 came without one.
Title: Re: Problems connecting Amiga to TV
Post by: SteveSMS on August 21, 2006, 07:24:00 PM
Mine is ok. Got a new TV set  :lol:
Title: Re: Problems connecting Amiga to TV
Post by: Stedy on August 21, 2006, 11:46:36 PM
Hi,

I have found with some video equipment, I have had to increase the active video from 0.7V to 1.0V for the monitor to receive a decent signal, otherwise the signals tears, similar to the pictures shown. I built a variable gain video amplifier to achieve this but there must be ready made composite video amplifier available.

The other possible issue is incorrect cable type, using 50 Ohm cable into a 75 ohm load, reduces the signal by one-third giving weird effects. Proper video cable should be 75 ohms by the way.

Ian