Cartridge "no sound" issue

[cater]

I use to play with my VIC 20 3/4 times a year and, recently, i discovered that some of my game cartridge now doesn't make any sound.
But some do.
So, as example, Vic Avenger or Slot are completely muted, while Cosmic Cruncher, Gorf and others play they regular "soundtrack".

I've just also bought a Penultimate+ Cartridge and here's same story: Pac Man no sound while Ms Pac Man have sound! Tetris no sound, Pole Position have sound... etc.

Not a TV or cable issue, i suppose, nor single Cartridge fault (otherwise Penultimate+ should have been working seamlessly)... where is the problem? What should i do?

[Noizer]

Check with another vic

[chysn]

It's possible that just one of the sound registers is out, and it seems like some cartridges work because they use different sound registers.

It would be instructive to write a BASIC program that gates each sound register and sweeps through its frequencies, so see if this is the case.

If one of the registers isn't playing, it doesn't necessarily mean that the VIC chip is faulty. It could be one of those transceiver chips going to one or more address lines of the VIC chip.

I think that the starting point is, you need to know exactly what's working and what's not with some good old-fashioned POKEing.

[Vic20-Ian]

I use to play with my VIC 20 3/4 times a year and, recently, i discovered that some of my game cartridge now doesn't make any sound.
But some do.
So, as example, Vic Avenger or Slot are completely muted, while Cosmic Cruncher, Gorf and others play they regular "soundtrack".

I've just also bought a Penultimate+ Cartridge and here's same story: Pac Man no sound while Ms Pac Man have sound! Tetris no sound, Pole Position have sound... etc.

Not a TV or cable issue, i suppose, nor single Cartridge fault (otherwise Penultimate+ should have been working seamlessly)... where is the problem? What should i do?

Try: (Don't type the bracketed text description)

Poke 36878,15
Poke 36874,200 (low range tone)
Poke 36874,0
Poke 36875,200 (medium range tone)
Poke 36875,0
Poke 36876,200 (high range tone)
Poke 36876,0
Poke 36877,200 (Noise sound)
Poke 36877,0

If one of those tones does not work it is probably a faulty chip in your Vic20

[cater]

Try: (Don't type the bracketed text description)

Poke 36878,15
Poke 36874,200 (low range tone)
Poke 36874,0
Poke 36875,200 (medium range tone)
Poke 36875,0
Poke 36876,200 (high range tone)
Poke 36876,0
Poke 36877,200 (Noise sound)
Poke 36877,0

If one of those tones does not work it is probably a faulty chip in your Vic20

Hi, thanks for the tip, i tried all pokes and i can hear all sounds so probably it's not a faulty chip.
Maybe some some cartridge slot connector partially damaged? Or... what else?

[chysn]

Maybe some some cartridge slot connector partially damaged? Or... what else?

Let's make sure all the volume register bits are getting set. With a sound audible do

Code: Select all

POKE 36878,8
POKE 36878,4
POKE 36878,2
POKE 36878,1

Can you hear all of those? You may need to crank your volume for 2 and 1, but can you hear them?

[cater]

Can you hear all of those? You may need to crank your volume for 2 and 1, but can you hear them?

Yes i can hear all bits.

As told i can't hear sound from some cartridge and from some games in Penultimate+; one of them is Avenger, and both original version and Penultimate+ version are muted (so not a specific cartridge problem).