[Coco] Coco 3 with problems, can anyone help me troubleshoot?
Mike Rowen
mike at bcmr3.net
Sat Feb 11 22:04:37 EST 2012
Looks like you already used audio on to test the cable. I had missed that in earlier post. Double speed issue sounds like a good one to check out.
On Feb 11, 2012, at 9:58 PM, gene heskett <gheskett at wdtv.com> wrote:
> On Saturday, February 11, 2012 08:58:10 PM Mike Rowen did opine:
>
>> Have you checked your cassette cable?
>>
> That is another possibility Mike, but if he can hear the tape in the
> speakers hooked _to_ the coco, then I'd like to think the cable is good.
> So the next question I'd have is, was the coco3 slowed to coco2 speed when
> that tape was written, and its also slowed to coco2 speed before the tape
> read is attempted?
>
> Frankly, the noise performances of the CCR-81 and look-a-likes have always
> disappointed me, a lot. The DC magnet erase and bias setups on those put
> so much noise and distortion on the tape that I have applied the same
> theory to those that we used back in Model T Ford days, which was said to
> have Christian Science oiling because you had to be a CS to believe the
> cylinder walls got enough oil. They never did.
>
> So while my metal tape capable Sony dual deck machine didn't have an
> interface that allowed its motors to be controlled by the coco, it was no
> problem to start the deck in record mode, then hit the return key to start
> the coco's output, stopping the deck when the prompt came back. I have yet
> to fail to read back such a tape even though it was only on one track of a
> stereo deck, even when that tape was played back in a GE copy of that
> CCR-81. I even mailed out a few copies of some stuff to others who
> reported they were flawless.
>
> So, that brings us back to his problem.
>
> Please give us a little better description of what that buzzing really
> sounds like. They should be rather raspy, with noticeable output from the
> tweeters if you have that fancy a speaker set. If it sounds like it has
> been through a low pass filter, with no more highs to drive the tweeters
> than you would get thru a phone circuit, I'd have to guess that one, either
> the head was dirty and the tape is not making good contact, or two the head
> is worn out, or the felt pressure pads in the cassette are missing.
> Obviously a fresh cassette and a fresh recording would tell that tale.
>
> The head being worn needs a quite strong magnifying glass to see if you can
> actually see the pole piece gaps where they come together, usually much
> much less than 0.001" and invisible even to a 100 power glass/microscope,
> so basically if you can see the gap, running vertically on the face of the
> head, its gone. This will also be visible it the supposedly cylindrical,
> well polished profile of a good head. If it looks like its worn unevenly,
> its safe to bet its worn out. Even good heads are like diamond phono
> needles, and gone in 500 to 1000 hours of use, unless it says Ampex 600 on
> the deck, they were much thicker and could hold specs for 30k hours.
>
> This is not to belittle Mark in any way. Its even possible that a coat of
> something atmospheric born is on the head after all these years, no fault
> of Mark's at all, and that a decent cleaning and letting a fresh cassette
> play through it full length to restore the polish might be in order. Since
> they are made of an alloy called mu-metal, its conceivable that they could
> also "rust" like iron would but I've no clue what color it might be if that
> is the case.
>
> Wikipedia says this about the alloy:
> Mu-metal is a nickel-iron alloy (approximately 77% nickel, 16% iron, 5%
> copper and 2% chromium or molybdenum)[1]
>
> That 16% iron could be an oxidation problem over the 20+ years since these
> CCR decks were made. On iron, we call that oxidation rust but I'd have to
> think its not anything but surface and an in-determinant color what with
> all the other stuff, like copper which also oxidizes over time. So will
> the chromium which is why your cars bumpers have a coat of nickle over the
> chrome to keep it nice & bright for a while.
>
> The wiki article does not discuss its oxidation modes or properties.
> Another site does allude to it with this statement:
>
> Mumetal is only moderately resistant to moisture and atmospheric corrosion,
>
> And that seems to about the extent of available data since the rest of
> those sites are interested in selling you some of it. ;-)
>
> However, beware of 'cleaning tapes' those things are like 320 grit
> sandpaper, every 10 seconds can take 50 hours off a heads life.
>
> If the full length pass of a new 2 hour tape fixes it, toss that tape, its
> now contaminated and having done its job, needs to hit the trash can.
>
> Hopefully I've hit the rest of the bases here.
>
>> On Feb 11, 2012, at 8:45 PM, haywire666 at aol.com wrote:
>>> I removed and thoroughly cleaned the gime chip and socket. no gook or
>>> noticable grime to speak of though when I started....
>>>
>>>
>>> Interestingly no more garbage screen bootups so cleaning the gime chip
>>> and contacts did something, but when I try to CLOAD the same problem
>>> happens (S character in upper left hand corner of screen) tape plays
>>> and machine locks in that state...
>>>
>>>
>>> Motor on/motor off commands work.
>>>
>>>
>>> audio on and audio off commands work.
>>>
>>> CSAVING appears to work. At least I think so... With audio on, I hear
>>> a bunch of buzzing when what I saved is played back...
>>>
>>>
>>> Steven
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: haywire666 <haywire666 at aol.com>
>>> To: coco <coco at maltedmedia.com>
>>> Sent: Sat, Feb 11, 2012 8:20 pm
>>> Subject: Re: [Coco] Coco 3 with problems, can anyone help me
>>> troubleshoot?
>>>
>>>
>>> 1) I have a ccr radio shack cassette I just got from cloud9.
>>>
>>>
>>> 2) When I use audio on commands I can hear stuff from the tape, but
>>> its been years since I heard a data tape. Sounds right from what I
>>> recall.
>>>
>>>
>>> 3) When I cload, the tape indeed starts, I get an S in the upper left
>>> corner of the screen. The tape stays on forever. The machine's state
>>> never changes, even when I left it for an hour.
>>>
>>>
>>> 4) I don't have a prerecorded tape to check. I am just now getting
>>> back to cocos (My first computer love) after many years off...
>>>
>>>
>>> 5) I don't think its high speed poked, I boot the computer the cursor
>>> looks regular speed, when I try it from clean cold boot this happens.
>>>
>>>
>>> 6) Someone else suggested pulling and cleaning the contacts of the
>>> gime chip. Just got back from radio shack, got an extraction tool...
>>> so I'm trying that now.
>>> Pulled the chip, both the chip and the sockets contacts look really
>>> dingy and dirty... so I hope maybe thats it. I'm going to go work on
>>> this now will post results.
>>>
>>> Thanks for everyone's help... Hopefully my poor coco3 will be feeling
>>> much healthier soon!
>>>
>>> Steven
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: Arthur Flexser <flexser at fiu.edu>
>>> To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
>>> Sent: Sat, Feb 11, 2012 6:54 am
>>> Subject: Re: [Coco] Coco 3 with problems, can anyone help me
>>> troubleshoot?
>>>
>>>
>>> You might narrow down things by using the AUDIO ON command to see if
>>> the tape sounds normal when it is saving and when you attempt to load
>>> a program.
>>>
>>> Also, make sure you aren't in the double speed mode; the cassette
>>> routines must be patched to work properly at that speed.
>>>
>>> When you say it "just hangs", I assume you've verified that the tape
>>> is advancing properly? Do the MOTOR ON and MOTOR off commands
>>> function?
>>>
>>> Art
>>>
>>> On Sat, Feb 11, 2012 at 5:12 AM, <haywire666 at aol.com> wrote:
>>>> I have a color computer 3 with some problems. I thought it was a cold
>>>> solder
>>>
>>> joint or something. Occasionally it would not boot right (I'd get a
>>> garbage screen) The real problem however is that once its working, I
>>> can save programs with csave to cassette, but when I try cload, I get
>>> an S on the upper left corner of the screen and then it just hangs.
>>>
>>>> Has anyone seen this before? Can anyone give me some trouble shooting
>>>> tips?
>>>
>>> Not being able to save programs (just bought a cassette for that
>>> purpose) is driving me kind of nuts.
>>>
>>>> Steven
>>>>
>>>>
>>>> --
>>>> Coco mailing list
>>>> Coco at maltedmedia.com
>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> http://five.pairlist.net/mailman/listinfo/coco
>>>
>>>
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> http://five.pairlist.net/mailman/listinfo/coco
>>>
>>>
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> http://five.pairlist.net/mailman/listinfo/coco
>>
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> http://five.pairlist.net/mailman/listinfo/coco
>
>
> Cheers, Gene
> --
> "There are four boxes to be used in defense of liberty:
> soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> My web page: <http://coyoteden.dyndns-free.com:85/gene>
> Toddlers are the stormtroopers of the Lord of Entropy.
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
More information about the Coco
mailing list