Hi!
I'm trying to repair a Bosch "getriebesteuerung", part.no.: 0 260 001 026.
Culprit is a crystal with a broken leg that needs to be replaced.
The crystal serve as an external oscillator for a Siemens B58468 CPU.
Problem is I'm not able to make out what frequency the readings on top of that crystal are.
It reads: 447NDK7I.
Anybody know what frequency this is?
Had no luck searching the net.. 🙁
I'm trying to repair a Bosch "getriebesteuerung", part.no.: 0 260 001 026.
Culprit is a crystal with a broken leg that needs to be replaced.
The crystal serve as an external oscillator for a Siemens B58468 CPU.
Problem is I'm not able to make out what frequency the readings on top of that crystal are.
It reads: 447NDK7I.
Anybody know what frequency this is?
Had no luck searching the net.. 🙁
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I have no idea what a getri.... might be. Car stereo? Home hifi receiver? Spark plug tester?
If we know the gear it works in, we might find the schematic for that. You never know what Elektrotanya has stashed away
If we know the gear it works in, we might find the schematic for that. You never know what Elektrotanya has stashed away
Appreciate your answers, but have to be certain about the frequency. This module controls gears in a tractor and the CPU (Siemens B58468) depends upon its external crystal accuracy.
Me too made that assuption that "447" ment 4,47MHz or was it "44,7MHz", "447kHz" and so on..
How to determine that crystal?
Have checked at NDK's site - no luck though... 🙁
Me too made that assuption that "447" ment 4,47MHz or was it "44,7MHz", "447kHz" and so on..
How to determine that crystal?
Have checked at NDK's site - no luck though... 🙁
Some thoughts:
contact the maker of the thing and ask what crystal they used.
If 4.47MHz is a very common one for other purpose like TVs, there is a very good chance the control people used it for their design. The CPU can run at a range of speeds, they write the software for specific speeds. I used to work in the coin-operated amusements field, and one major brand of pinball just used 4MHz color crystals for its CPUs.
If you wonder about a part, don't just "check their site", CONTACT them and ASK. Web sites rarely cover every part a company makers or uses.
So so far you know 4.47MHz is a common part, that probably also means they are not expensive. Your doubts as to 4.47 or 447 or 44.7 are legit, but the differences are factors of 10 or more. So try a 4.47MHz in there and see if it boots and passes self-diagnostics or whatever wakeup routine it has. If that turns out to be wrong by a factor of 10 or 100, then chances are it won't work at all.
contact the maker of the thing and ask what crystal they used.
If 4.47MHz is a very common one for other purpose like TVs, there is a very good chance the control people used it for their design. The CPU can run at a range of speeds, they write the software for specific speeds. I used to work in the coin-operated amusements field, and one major brand of pinball just used 4MHz color crystals for its CPUs.
If you wonder about a part, don't just "check their site", CONTACT them and ASK. Web sites rarely cover every part a company makers or uses.
So so far you know 4.47MHz is a common part, that probably also means they are not expensive. Your doubts as to 4.47 or 447 or 44.7 are legit, but the differences are factors of 10 or more. So try a 4.47MHz in there and see if it boots and passes self-diagnostics or whatever wakeup routine it has. If that turns out to be wrong by a factor of 10 or 100, then chances are it won't work at all.
Thank you for your reasoning, Enzo.
I will try that 4.47MHz crystal first and see what happens.
Trying to contact those big companies with these kind of questions, is like yelling in space..
My thought posting here was just that I believed this kind of component interpretation was just as easy as reading a ceramic capacitor for instance.
I will try that 4.47MHz crystal first and see what happens.
Trying to contact those big companies with these kind of questions, is like yelling in space..
My thought posting here was just that I believed this kind of component interpretation was just as easy as reading a ceramic capacitor for instance.
If you can make temporary contacts on the stubs, you can measure the frequency and pick the correct part right away without enduring the trial and error charade....
True story, KatieandDad! Only 4.0 and 4.43 are available in that segment, -and thanks to Elvee for that tip! However this units crystal cannot easily be measured in progress at the workbench. This units connector have a NUMEROUS amount av pins (more than 60) and God knows what goes where..
Short story is that this vehicle (tractor) ran down a hill and into seawater (with battery power connected).
I've managed to repair several broken lines and have replaced other components that were "due", but if I just put a "random" crystal in place for the broken one, I cannot be SURE if thats the real new culprit or if my previous repairs are to be questioned.
Maybe I just hook it up while measuring Hz in transit, hehehe 🙂
Measuring crystals out of circuit I believe will call for some gears I do not obsess. I do however have both a frequency counter and a scope.
My last thought is that maybe 447 means: 44 + 7 times zero's? Then we have 440MHz.. no way in this oackage!
Think I just assemble it the best way and try out Elvee's tip. The leg broken will give one challenge as for connection though...
Thanks again! 🙂
Short story is that this vehicle (tractor) ran down a hill and into seawater (with battery power connected).
I've managed to repair several broken lines and have replaced other components that were "due", but if I just put a "random" crystal in place for the broken one, I cannot be SURE if thats the real new culprit or if my previous repairs are to be questioned.
Maybe I just hook it up while measuring Hz in transit, hehehe 🙂
Measuring crystals out of circuit I believe will call for some gears I do not obsess. I do however have both a frequency counter and a scope.
My last thought is that maybe 447 means: 44 + 7 times zero's? Then we have 440MHz.. no way in this oackage!
Think I just assemble it the best way and try out Elvee's tip. The leg broken will give one challenge as for connection though...
Thanks again! 🙂
Do not try to make an in-circuit measurement: just build a one transistor Colpitts oscillator and measure the OP frequency.
It will be some ppm's away, but that is completely unimportant.
The number indicated may be related to the actual frequency -or not-: it could be part of a P/N° or something similar
The processor is a variant on the 80C517, so not more than 16Mhz
14.4756 MHz is a standard value, so a possibility
14.4756 MHz is a standard value, so a possibility
I've never known any manufacturer have a specific crystal built only for them (OK some MOD products might have bespoke crystals). This will be a possibly modified CPU with a standard crystal.
Could this be the case?
http://www.anglia-live.com/netalogue/pdfs/hud/datasheets/frequencypg28_29.pdf
XT447 is 9.8304MHz
I've also found an identical crystal in my "stock" which reads 419NDK. Believe this might be the 12MHz one?
Not the most scientificly approach I agree, but it does make some sense, or?
http://www.anglia-live.com/netalogue/pdfs/hud/datasheets/frequencypg28_29.pdf
XT447 is 9.8304MHz
I've also found an identical crystal in my "stock" which reads 419NDK. Believe this might be the 12MHz one?
Not the most scientificly approach I agree, but it does make some sense, or?
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