mbsid no sound. all test passes

Hi

Im stuck. I have made the initial test to the SID module. I have:

  1. uploaded the interconnection program, and all tests went fine.

  2. Tried 2 different 8580.

  3. tried with 2 different SID modules.

  4. Made sure my “mono jack plug” is correctly installed.

  5. Uploaded testtone.

Now im stuck, i dont get any sound, and i dont know what to do now???

I hope some of you have a bright idea.

/Carsten

Hi,

If you don’t hear any sound (even no digital background noise from the SID), then it’s very likely that either the transistor is not connected correctly (compare it with the pictures), that there is a short at the audio out stage, or that the voltage at pin #28 is not 9V

Best Regards, Thorsten.

You´re right. The voltage drops from 5V to about 2.8 after 7809. Should i look for shorts, change the 7809, what?

I dont think its a short, because i have made 3 boards at the same time, and they all show the same failure.

I could post some pictures when my camera has recharged?

i was sure i had gone over all measurings, but i guess i missed this one.

/carsten

The voltage before the 7809 must be higher than 9V, the voltage after the 7809 must be 9V

Best Regards, Thorsten.

With the optimized PSU? How can it be higher than 9V before 7809, when the input is 9V.

Because if you mean when testing with 15V connected to J1, then it the test passes, and that is not the problem.

I send a picture with this time. The back picture will probably not tell very much (i have actually improved a lot since this. I have a new and much better iron. My Dinx4 looks good)

About the front: I had my doubts about all the capacitors, but i think i made it right. Would you please have a quick look. Dont mind the audio in bridge, its just temporary.

Hi,

jumping in with some annotations.

First, to clarify: The optimized PSU gives you an output-voltage of 14v wich is fed in J1 of the SID-Module. The 7809 on the SID regulates the voltage down to 9v needed by the 8580. A regulator always needs a little more voltage to work properly.

On your board you have marked a cap with 171. This should be 471 (470 pF).

The two white foil-caps you used making me wonder. Are these really 1nF?

Mike

Quoting Modularcomplex:

On your board you have marked a cap with 171. This should be 471 (470 pF).

The two white foil-caps you used making me wonder. Are these really 1nF?

My bad about the 171/471 thing, it was hard to read. It is infact a 471.

The white foil-caps says: 1n J 100 - i bought them from Mikes electronik seite (it wouldnt happen to be you?), and i really had my doubt about these, but they were the only ones adding up remotely.

About the PSU. i though i had one line feeding 9V AC connected to J1, and another line fedding 5V DC connected to J2.

Maybe i constructed my PSU wrong. I just tried testing the one line i though would give 9V AC, and it gives me 5V DC?

Nice to see some other ucapps people in my threads, i was starting to feel i was using TKs expertise to much  ;D

/carsten

Your answers are a little bit confusing, I don’t know if we are talking about the same things…

First you wrote:

You´re right. The voltage drops from 5V to about 2.8 after 7809.

Now you write:

How can it be higher than 9V before 7809, when the input is 9V.

Because if you mean when testing with 15V connected to J1, then it the test passes, and that is not the problem.

So, what is the voltage between ground and the input pin of the 7809, which is stuffed on the SID module?

And which test passes when 15V are connected to J1 - do you hear a sound? Or do you mean any other test?

Please also answer Mike’s questions

Best Regards, Thorsten.

When 15V are connected to J1, the first voltage test in the soldering guide of the SID module passes. Thats what i meant.

The voltage drop from 5V to 2.8V is when im connecting the SID and CORE to my C64 PSU.

I allready answered Mikes question, but here goes:

The white foil-caps says: 1n J 100. Nothing else.

To further explain. I had my doubts about these, but they were the only caps left (except what Mike had stuffed in for either 8085 or 6581).So i figured it had to be them.

/Carsten

Hi Carsten,

the “1n J100” are ok (means 1nF 5%), couldn’t read the markings on your first picture.

About the PSU. i though i had one line feeding 9V AC connected to J1, and another line fedding 5V DC connected to J2.

Maybe i constructed my PSU wrong.

Hmm, thats my conclusion too. There seems to be something wrong with your PSU-Layout.

On the other hand, you dont seem to really understand what the optimized PSU does. (Please dont get me wrong, just want to help)

Here is what it should do:

On the input side are 9vac and 5vdc. On the output, you will get the 5vdc for the core and sid-modules and 14vdc for the sid-module.

Please measure directly on the output of your PSU-Circuit if these voltages are right.

Mike (not the one from mikes-elektronikseite.de)

But i believe i have found the problem. Check out the bubble on the rectifier of the PSU.

I have been very confused about the PSU, so you´re absolutely right. No hard feelings :slight_smile:

/Carsten

I did just that before you wrote to me. And added up im getting a little under 14V, and after the 7809 i little under 9V (actually closer to 8 ).

Which 7809 do you mean? On the psu itself? The output of this 7809 should give the 14v. Where do you measured the 14v then?

I dont know if the rectifier is defective. Could be, but first check your circuit if it really corresponds to this schematic.

Mike

shit. sorry. the 7809 on the SID.

As you have probably allready figured out. I am a total newbe to electronics. Hence, i have done all that was in my power to understand schematics and build the PSU accordingly to the PDF file. I think i have done it right.

Question: if the rectifier of the PSU IS broken, wouldnt the rectifier of the SID module do the same.

Forget about the 14 Volts. I think im tired, i should probably let it rest till tomorrow. Im not sure im troubleshooting very well. i think im confusing you with my answer. And i totally messing around with everything here.

I will have a look at the PSU again tomorrow, and return to this topic.

Thanks

Ok. this thread is suddenly about a whole different problem than what it started out with. I have been trying to make the c64 optimized PSU, but i dont have any luck.

Altitude provided me with a good quickview

http://www.midibox.org/forum/index.php?action=dlattach;topic=7626.0;attach=348;image

which i think i followed correctly. None the less i dont get the right meaurings. Infact i get nothing from the 5V output, and about 1V at the 14V output. Thats even worse than before, where i got 5V from both outputs.

I am posting 3 pictures in the hope that someone will comment on them.

(i have used GIMP, which is new to me, so i couldnt make it better than this)

Thanks

Carsten

PS: i bought a new rectifier, just to make sure

Sorry about that.

Hi Carsten,

one thing I see is that you seem to misread something on Altitudes schem. The Foil-Caps are marked with “.33uF” and “.1uF”. The dots mean a decimal-point, so the values should be 330nF and 100nF.

The circuit itself seems to be ok, but I dont know if the pin-assignment of the input-connector is right. Please measure if the input-voltages are the right ones, too.

Mike

I think the caps are ok. One says 0.33 other says: u 1 K 100.

Its a mistake in the picture.

About the input connectors: This could be an important failure. I can measure 5V at the 5V pin, so i dont have any doubts about which ones are ground and 5V, and that pretty much gives away where the 9V AC is placed. But i cannot measure anything from the 9V pin, not with V== or V~.

The 7809 gets incredibly hot - but i have read that that is normal.

Question: When i measure at V~ on 200, 14V will look like 1,4 V right? cause that pretty much what im getting at the 14V output (which is weird, when i cannot measure the input)  ??? Puzzled

Still no output on the 5V out-pin

/carsten

One more thing to make certain,

Is this right:

If you measure 5v, the black probe of your voltmeter is gnd, if you measure -5v, its on the red probe.

There are two 9vac-pins, measure them with the V~ option.

The 7809 should not get “incredibly hot”. It gets warm when operated properly.

When you are trying to measure 14v with V~ you got something wrong, the output should be 14v- (dc). Only the 9v-input is ac.

The 0.33 cap is ok, that is 330nF. The other one is a 1uF, not a 100nF.

Mike

PS:

Your graphic is nearly ok, only thing to mention is, that both of the upper two pins are used for 9vac.