Conference hydra::amiga_v1

I did this a while back (I'll assume that the A200 has a DB23 connector
wired the same as the A1000):

	PINS	USE
	------	------
	3	RED	___ pair these up using coax leads
	  16	GND	_/
	4	GREEN	___ ditto
	  17	GND	_/
	5	BLUE	___ ditto
	  18	GND	_/
	10	CSYNC	___ ditto
	  20	GND	_/

If you can't get a DB23 connector, take a DB25 (standard RS232 connector) and
hacksaw the last two pins off (that's what I did). For each of the coax's
you'll need a BNC connector for the back of the VR241.

Note: 	you HAVE to use coax or the RFI from unshielded lines will destroy any
	radi�o/TV reception in your house.

By the way... I didn't like the VR241 and bought a SONY KV-1311CR instead.


Good luck!
dave

If you can't find a DB23 connector any where else, you can order them
from:

	BCD
	Jim Black
	P.O. Box #1224
	Bartlesville, OK 74005

	Phone: (918) 336-1784

Price is $3.00 plus $2.00 Postage and Handling.  I've never ordered
anything from this guy:  I've just seen his ad in Amazing Computing.
(The ad copy is "We have those funny connectors for the back of the
Amiga!")

    Thanks for the info. Sounds like a real hack job. As to buying a
    DB23 connector---unfortunately I'm in the UK, and doing mail order
    through the States might be a bit iffy.
    
    The good news, is that I intend to get a better monitor next
    year...when my bank manager has managed to recover from me buying
    this.
    
    Martin
    

    You can order one from Germany (should be easy as both are in EC).
    Or if you happen to visit a training course in Munich, you can buy
    one off shelf in one of the shops in Schillerstrasse.
    

    Could you comment a little more on what the display looks like on
    the DEC display.  I understand that interlace looks quite bad, but
    how about the other graphics modes.  Is the display capable of
    displaying all 4096 colors?  How's the aspect ratio?
    
    I am thinking about buying a used A1000 for work, and have an old
    Pro380 (ugh!) with a color monitor sitting on my desk.  If I can
    get by with this monitor (I have the Sony KV1311CR at home) I would
    save a lot of money.
    
    Any more comments?
    
    Randy
    

    I use a VR241 and It is OK!!!!  A long persistance monitor would
    be nice, but.....
    
    If you need a connector (23pin) or cable info... let me know.  VR241
    would be ideal for at work....
    
    
    John
    

    Minor point:  The VR241 is very heavy.  I wouldn't recommend setting
    one on top of an amiga 1000.

    re .7: I haven't had any problems. I think the max load is speced
    somewhere and the VR241 doesn't come anywhere near.
    

    
    I have just wired up a cable using 550.1 advice from A500 to VR241-A 
    and escaped from the fuzzy land of TV monitors. Everything works like
    a charm, including "overscan" (wide display used in Australia on PAL
    system) - at least equal to the "standard" monitors.
    
    A bit more detail below, to help other non-engineering types like me:
    
    1. There are two sets of 4 BNC connectors on the back of the VR241 -
       75 OHM  and "Other".
    
       Normally a Rainbow or VT240 terminal (which I also use) connects to
       3 R/G/B connectors on the "Other" side. The "Synch" switch is
       set to "INT" internal, which means you dont need a 4th BNC.
       This is apparently because in this setup, the source signals from
       VT240/Rainbow are digita RGB, which can only handle a max of 16 colours.
    
       The Amy pins 3/4/5 however generate Analog RGB signals (standard
       4096 colours). If these are connected to the 75 OHM connectors,
       along with the 4th additional "CSYNC" composite sync (combined
       horizontal/vertical), and the "Synch" switch is set to "EXT" then
       you will get a perfect image!
    
    2. The cable components cost me $30 (Australian) at my local electronics
       store.
    
       Component list:  6m small co-axial cable (inner wire + shield)
    				(cut into 4 x 1.5m)
    			1m 10mm heat shrink plastic tube
    
    			Alternative: If you can find a cable with 4-coax
    				     leads internally, then thats better.
    
    			4 BNC connectors
    			1 DB23 23 pin connector
    			1 DB23 plastic housing
    
        Solder up the 4 BNC connectors and then thread the coax leads
    	one at a time through the heat shrink tube. I needed a length of
        stiff copper wire to draw the last couple throgh.
    
    	I made my cable about 1m long, adding 10cm free from the tube at
        the BNC end for reach. I dont know what the maximum "official" length
        allowed is, but this seems to work OK!
    
        Then solder in the 8 leads on the DB23 connector, flame the ends of
        the heat shrink tube, and you have a servicable cable.
     
    3.  After connection, I had to take the plastic  housing off my VR241
        and adjust the vertical hold and focus with a screwdriver to get
        a stable screen. These adjustment controls are marked, so you can
        easily find them. The focus can actually be adjusted with the
        housing still on if you have a very thin screwdriver through the
        tiny hole marked X at the rear.  Make sure the monitor is warm
        first.
    
    4.  Of course there is no monitor loudspeaker. I have my sound connected to
        the "Auxillary" of my stereo amp, so this doesnt make much
        difference except that now I cant use my radio at the same time
        as the Amy! 
    
    5.  Having been inspired, I now presume the same principle can be used
        to wire up a monochrome VR201 (Rainbow/VT240) monitor if I wanted
        to. If I'd thought of that earlier then I wouldnt need to have
        waited all year until I found a colour monitor for straight Amiga
        B&W word processing.  I assume I would need to connect up 3 or 4 
        of the A500 wires for that - monochrome, +12V and some grounds.
        The VR201 needs external power.
    
    	If anyone has the VR201 pin specifications, please add it here.
    
    6.  I have both my A500 and Rainbow connected to the VR241 - on
        left SRGB and right RGB respectively, and use the selection switch
        on the rear to move between them.
    
    Regards.
    
       

I would not recommend trying to use a vr201. It would have
to be drawing considerable power through the 12v line, more than
a mere 500 could hope to supply I expect.

I supose if you used an external power supply for the monitor...

A more hardware orientated person care to comment ?

Mike
(in Adelaide)

    Hello,
    
    Thanks for this neat description in .9 but i'll like just one/two more
    detail(s):
    
    I have a 3bcn cable on one end and seven wires(I have cut the cable
    before the 15 pin connector) on the other side: 3 RGB and four other.
    
    How do i plug what into what. I can assume that one is for
    the ground, one for the sync with the green but don't know which ones
    are for what the cable is from a DEC cable ref BCC17-06.
    
    I could otherwise cut the other side and just have a seven wire cable.
    Then how do i pin the BCN is it the core of the wire or the tread
    around that i should use ?
    
    Mant thanks Patrick 

�    I have a 3bcn cable on one end and seven wires(I have cut the cable
�    before the 15 pin connector) on the other side: 3 RGB and four other.

    Unfortunately you need *four* BNC connectors for the VR241 end; the
    fourth source being CSYNC on the Amiga end and EXTERNAL SYNC at the
    monitor end. As illustrated in .1:

        Signal     DB23     Coaxial      BNC
         Name    Connector   Cable    Connectors
	------   ---------  -------   ----------
                 _____
                 |    \ 
                 |     \ 
                 |      \              /====
        RED      | 3    |--------------------   <-- center pin
	GROUND   |   16 |--------------\====   <--- shell
                 |      |
                 |      |              /====
        GREEN    | 4    |--------------------
	GROUND   |   17 |--------------\====
                 |      |
                 |      |              /====
        BLUE     | 5    |--------------------
	GROUND   |   18 |--------------\====
                 |      |
                 |      |              /====
        CSYNC    | 10   |--------------------
	GROUND   |   20 |--------------\====
                 |      /
                 |     /
                 |____/


�    are for what the cable is from a DEC cable ref BCC17-06.

    You won't be able to use this cable unless you add another BNC
    connector as mentioned above (in addition to the RGB trio you have now).
    
�    Then how do i pin the BCN is it the core of the wire or the tread
�    around that i should use ?

    The "signal" lines (red, green, blue, csync) go from the DB23 connector
    pins 3,4,5,10 on the Amiga side to the "core" or center conductor of
    the coax cable to the center pins of the BNC connector at the monitor
    end. The outer "tread" or shield conductor of the coax cable goes from
    pins 15,17,18,20 on the Amiga side DB23 to the shell of the BNC
    conectors.

    Apologies for the crude drawings...

    Pete