Atari 2600 Static Sound Problem
| March 15th, 2020
Since I was young I always wanted to own an Atari console. We didn’t have one but our neighbors did and we used to go to their house to play on the one they had. So in 2019 I decided to buy a vintage gaming console and I found a good looking one on ebay. After a week of bidding I won the auction.
A month later the console arrived, first issue I faced was connecting it to my old PAL tv. The coaxial cable didn’t fit, though it seemed it will, but it just didn’t. So I started looking locally for adapters and after some search I managed to combine couple of coaxial adapters into one (see below gallery)
After connecting all parts with the TV. I had to search for the tuning through the TV menu. So I sat the channel option on the console to channel 3 and went into the menu settings of the channel and started searching. My setting are in the image shown bellow
After successfully tuning into the right frequency I immediately noticed a problem with a very load static sound. Searching the web I came across the service manual for the 2600 4 switcher (Download here). At first it seemed out that the issue is with the variable inductor, part L201, seen in the image below
Since the marked parts are adjustable inductors, I tried to adjust their frequency with a 2mm allen wrench but found out that the inner adjustable piece was broken into pieces. I search the internet for a replacement but only found it here: https://www.bgmicro.com/COL1147.aspx
I ordered a couple of inductors since it was very hard to find them and I don’t know until when they will be available.
When the order arrived, I decided not to change the whole inductor but rather to change the inner piece and keep the original one. So I desoldered the part, took out the broken pieces inside it and installed the one from the new inductor and put it back. I also noticed that their is another inductor inside the RF module which also had broken pieces inside it (the small rectangle on the bottom right in the above image) , so I did the same for it.
Unfortunately after doing all that, the issue was still there. Jumping the two pols of the inductor seems to make a it bit better, but the problem was still there, see video below:
Further investigation lead me to the audio caps and resistor, see image below
1- R207 – C010821 – Resistor 1 /4 W 4700 Ohm
2- C206 – Cap. Polystyrene 820pF (50V)
3- C207 – Cap. Polystyrene 820pF (50V)
4- C208 – Cap. Ceramic Disc. OluF (50V)
I am now looking to replace those parts and see if this will solve the issue. Found a refresh kit for atari 2600 here
Meanwhile we keep playing games with a muted sound
