any other offers?:unsure:
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any other offers?:unsure:
@AmiNeo
you can put up a wanted add in the Amiga -> Wanted section to get more hits if you would like.
Although one cannot garuantee that its a capcitor problem (as it could be a number of other things) its the most likely of cuplrits as 15+ years even of a moderately used A1200 is more than they were originally designed for.
for the moment thought, sit back - relex and enjoy your A600, theres plenty of fun to be had with that I can promise you.
Save some pennies and have a chat with the guys that rkauer mentions =)
juvuk mutters to himself "pah A600"
LOL, yea i know. the 600 is great, was my only amiga when i was younger but theres a 1200 in the room and i can't use it... :censored: lol.
I will hang on and try those other ROMs first if scrappy doesnt mind still sending them. Afterall there is a chance its not the caps, however small.
Out of curiosity how much wattage does a 1200 need from the PSU for a stock unit? Ive been thinking that although unlikely, perhaps the PSU isnt up to the job...
And broadening my options... and i know were not suppossed to mention costs due to price driving but approximately how much would it cost me to replace the motherboard altogether? Say if i was to find a spare working one on the for sale boards one day.
Just a ballpark will do... I'm at a disadvantage being fairly new and not used to seeing a lot of things on the boards for sale yet so i have no history to base it on...
---------- Post added at 11:51 ---------- Previous post was at 11:48 ----------
And lol JuvUK
best advise m8y, do a search on ebay for A1200, that should get you a rough idea of prices
:cool:
All i can find on there are full systems though.
No motherboard onlys or anything like that. Nevermind if you cant say ill just keep an eye out.
@AmiNeo, your parcel was sent this morning matey.
If you do find you need a new motherboard and you cant find one on the forum give the ebay seller airey36 a message via ebay.
He splits machines up all the time and i'm sure he'd be able to sort you one out.
Mike
Quote:
Originally Posted by Zetr0
I will test the new roms before posting a wanted ad for the service.
Thanks Zetr0 :)
Quote:
Originally Posted by scrappysphinx
Heh, I've actually had a couple of motherboards for the A600 off him recently. He's about the only guy on Ebay that sells amiga hardware other than full units. Was thinking of giving him a shout.
It's while I was dealing with him that I stumbled across AMIBAY :D
... And Amigakit...
---------- Post added at 18:50 ---------- Previous post was at 18:49 ----------
...And cheers Scrappy! :thumbsup:
I was thinking a new intact board may be cheaper than posting the thing, paying for caps replacement and then shipping back to me. Especially if it turns out to be something different altogether... What u guys think? What would you do? I need to spend a little as poss, and unless im shelling out for a new iron, replacing caps myself wont be an option.
repair/refurbishment is a better option in my opinion, otherwise you could well just keep buying boards that need work doing to them now or in the near future.
Despite that you have no video on your A1200, is the machine actually working - ie, will the drive actually respond and start loading if you put a bootable disk in?
If you go for a replacement motherboard, you will need a 2B version otherwise the floppy drive you have wont work. But the 2B is the lesser desirable version so you might get it cheaper than other revisions.
If you do go for a different version you will have to get a floppy drive also.
No theres no response from the floppy atall when a bootable disk is in the machine. It clicks once regardless of whether there is a disk or not in it when the power is turned on though but thats all.
I kinda agree with the refurbishment thing but if it turns out its more than just caps...
What a dialema lol. :roll:
---------- Post added at 09:19 ---------- Previous post was at 09:15 ----------
Floppy drives are motherboard specific?!? I wonder if thats why theres no response from this one...
i also didnt know floppy drives were specific to motherboards, i thought that a floppy drive was a floppy drive and would work with any revision motherboard
Evilbay Airey got back to me and said he doesnt test them beyond booting, so couldnt garantee anything.
Buying one from him could land me in the same boat if caps is the only problem.
And may i ask why the 2B is the least desirable? :dry:... lol
---------- Post added at 09:39 ---------- Previous post was at 09:28 ----------
Quote:
Originally Posted by scrappysphinx
Yea, i could understand 1200s not working with 600s or something but 1200s not working on 1200sl!? I'd like to know why that is... :blink:
The A1200 was sold by two companies over its life time, Commodore which went *pooff* and later Escom / Amiga Technologies. The 2B could be the Escom revision of the A1200 as opposed to Commodore for the previous revisions. Escom uses a modified PC floppy drive which can cause some incompatibilities as the modification was both board level and at the drive. Then there is the issue of accelerators and 2B compatibility which affect the boards value.
I thought the escom board was 1.d4 board?
and even though they used modified pc drives i still believed they worked on all revisions?
AFAIK the Escom 1200 floppy drives were missing the _RDY signal, so the board had to be modified to suit. If you use an Escom floppy drive on an earlier board I would think that some game bootloaders and maybe xcopy might not work properly.
From reading around the last of the 1.d4 s were sold to escom which they modified to work with pc drives and the 2b is a fully escom revision.
The 2B can be modified to work with standard amiga floppy drives though.
http://www.softpres.org/article:hard..._fdd_connector
Quote:
Originally Posted by TheoryBoy
Intersting, i was aware of the manufacturing history of the 1200 as per the ESCOM reproduction but never knew they changed this much...
---------- Post added at 11:52 ---------- Previous post was at 10:39 ----------
Hey scrappy, your parcel just arrived...
New ROM new Cable, same problem... :|
Just to clarify, nothing changed, lol. I am getting the same output as with the composite cable, and the ROMs didnt change a thing...
@AmiNeo sorry bud thought the video port might have worked.
Looks like your either after a new board or someone to repair yours.
Ok, no probs, you want the bits back bud?
you can keep em if you like, i only kept them as spares for testing machines i buy so i don't have to keep disconnecting my main machine
Ok well i appreciate it, im sure they'll come in handy.
If you ever need em back just holler :)
i still think the board needs some work after the roms were moved from board to board etc
What you mean Juv?
---------- Post added at 12:24 ---------- Previous post was at 12:23 ----------
Telling someone theyre doing it wrong isnt helpful unless you say why, lol :lol:
from what i've read in this thread, A600 rom was plugged into the A1200 board and visa versa, you don't seem to be completely sure of the orientation, i have killed a mobo in the past by fitting the roms correctly, that's all i'm saying
cheers, JuvUK
@AmiNeo
I truly hate seeing this thread go on without resolve =(
I cannot promise anything - but I think I can help you out - however time is pretty damn pressed for me.
I have sevearly things to sort out and these would come first.
2x A1200 timing fixes - Blankstare
1x A600 2MB Chip Piggy Back - Juv
1x MiniMig - Arnljot
1x 030 track repair
2x A4000 motherboard repairs (caps and logic)- Juv UK / Me
3x A1200 motherboard recaps - ME
A2000 PSU rebuild - ME
A2000 Hybrid Build - ME (on hold - waiting components =()
*(Special suprise for TokyoRacer)*
If you can wait. then hit me up on PM, we can see what we can do on the cheap.
I think the only thing now is to make a good visual inspection of the board, checking for bent chip legs, traces of capacitor leaks, broken traces. especially checking the legs of chip at U4 (the one marked hp) in case of improper indivision installation in the past.
Other than that.. well another board I'd say
Oh an Zetr0 as I have you here, there is no need to send me that a500 zorro adaptor, I ordered one from tom with a different zorro card.
Cheers
Quote:
Originally Posted by JuvUK
You can kill a motherboard by incorrectly installing 2 EPROM chips in the wrong places? How does that work?
With them not even initialising however i doubt it has changed anything either way.
---------- Post added at 12:49 ---------- Previous post was at 12:42 ----------
For the record i wasnt stupid enough to put them in backwards or in the wrong pin holes... As far as im aware an EPROM shouldnt damage anything if its in the correct place even if the data is incompatable?
---------- Post added at 12:50 ---------- Previous post was at 12:49 ----------
Hey Zetr0, I'd really appreciate that bud. let me check a few more places and if i get no joy i'll send you a PM.Quote:
Originally Posted by Zetr0
In my experience, if you correctly plug in an EPROM with the wrong data, the Amiga won't boot but no damage should be done. If you plug in the EPROM incorrectly, you're quite likely to kill the EPROM, but shouldn't do any permanent damage to the board. Still, killing EPROMs is annoying and every ROM change is putting wear-and-tear on the ROM socket.Quote:
Originally Posted by AmiNeo
Now that I can live with, lol. Installing an EEPROM with the wrong data on shouldnt really be any different physically to putting a hard drive into a PC without a correct file system.
Correct me if i'm wrong but an EEPROM chip is an EEPROM chip as a hard drive is a hard drive. If they're designed for the same use and carry same voltages, even if the data is wrong they shouldnt be able to damage anything provided the pins are where they're suppossed to be in relation to voltages.
Its not that, its just that swapping roms between 600<>1200 conveys a negative image :D Such that imagining incorrect rom insertion is not outside the realm of posibility.
Rofl, yea I get what u mean. But I wouldnt do anything that I thought could damage the board even in the slightest.
Now put them in backwards and I'd be agreeing with you, lol. :lol:
CompTIA A+,
CISCO IT Essentials,
MCP (User Support),
CISCO CCNA (Expired :lol:),
...:cool: lol.
To end the discussion and going back to main issue:
ESCOM AG used 1D4 and 2B boards (pretty much every board that was left behind in Commodore stores/shed), but they modify ordinary pc floppy disks to operate in the boards, which forced they to hack those boards too.
But it is easy to spot the problem: hook a normal Amiga drive (it will work; OK, sort of). Put some floppy that needs the diskchange and ready signals, like State of the Art demo (two disks). If when the demo asks for the second disk and you insert it and nothing happens, the board is an ESCOM unit.
________________
Now, I still think your problem is just the capacitors.
A way to tell: with a magnifying glass check the solder pads of they. The solder must be perfectly brighting, and not a bit faded/wet/darker than other solders around.
Also, if you touch one of the solder pads with a solder iron, the smell from leaked capacitors is very similar to cat urine/rotting fish. Lovely, huh?:twisted:
BTW: the most affected capacitors on A1200/600 boards are the ones near the floppy unit (op-amp audio filters), the audio output ones (on the back of the audio jacks), the lonely chap a bit over the PCMCIA connector and at last the silver ones very near the IDE connector. Check for leakage and/or bulges (the top of the capacitor will look a bit "rounded" instead flat).
Theres nothing obvious in the way of bulging or discolouration that I can see... I will post some piccies of close ups of these areas tomorrow however while having a closer look.Quote:
Originally Posted by rkauer
Thanks again for all your help and comments guys. I'm learning more about the wonderful amiga with every post :)
Hey guys, I had to find my charger to recharge batteries for my cam, sorry about ther delay, heres those pics. I hope theyre good enough, I cant really see much myself thats obvious... Hopefully ive covered all the key places mentioned in the post above, if not give me a holler and I'll post another couple if necessary.
I cant beleive the little bits of dust that are showing up in these macro pics, It looks spotless to the naked eye...
yea the flash reveals all dust lol.
Yes much better photos than before.
Could you take a good overall shot of the board and close up of U1, U4, U20.
sure, bare with me theyll be up within half an hour...
Just a point to mention guys,
if the electrolyte has dried up - you wont see any damage on the board and the capcitor just wont function.
If you want to isolate the capacitor(s) in question you will need to use multimeter and test the positive and negative leads for charge with the A1200 powered on - you will also need to know what charge you should be getting to the actual reading.
you must start at the "power - in" jack and sequentially test each capacitor - this is because if capacitor before the one your testing is not pumping correctly it will effect those left in the chain - so start at the begning and work your way up.
This will take you atleast an hour, please be carefull not to short anything or hurt yourself.
If you can test the capcitors then please write the capacitor number (usually labled [Cxxx]) and the voltage reading - I shall hit my books in the lul momnets to see what that cap should be pumping out.
dont worry if you get negative volts thats to be expected on the audio circuit, just write down what readings you get.
To help, build up a result table:
That will help with diagnosiing the culprit.Code:Cap No. Rate V+ V-
C128 47uf +5.1 -5.1
C132 10uf +4.98 -4.98
.... and so on
.... and so on
However the ammount of time taken you could replace all the capacitors quicker.
Hey Z, unfortunately i have neither a multimeter nor a soldering iron precise enough to remove these buggers to hand.
Here they are, had to do the 'overall shot' in 2 halves or it kept coming out blurry.
Has everyone run away? lol :lol:
I was looking for bent pins or physical damage. Nothing really to see.
I really hope its just the caps that are at fault, but I am not convinced.:unsure:
Quote:
Originally Posted by TheoryBoy
What else do you have in mind?
Other than the caps having dried up I have no clue what it could be. I have gone over the board a few times now, and physically I cannot see any flaws whatsoever. Though I'm not exactly an electrician or anything, I've seen plenty of boards in far worse physical shape that boot up, lol.
C305 and the audio ones clearly (OK, not so clear) leaked.
How can you see that? Where?
Bit of discolouration of capacitors legs.
Or too much wine to cope with the cold is making here! I use to love Winter...
Hmmm... sure its not just the pic ? I will post a close up of that cap shortly...
Here we go...
Nope, nothing apparently wrong.
Can you please take a close picture of the components on the back of the RGB connector and also the area around the CXA1145 (video encoder)?
The CXA1145 is located between the IDE connector and the power supply area. Also around the DSP chip (between LISA and the CXA).
Did you ever disconnected something from the RGB port with the Amiga turned on?
Also I think you must check all the voltage levels with the Amiga on. A digital multimeter is a very cheap acquisition and will ease the problem debugging. Buy one of those less-than-£5 chinese cr4p, it will be enough for your immediate needs.