Hey All,
I've recently starting using an Apple IIe. I'm having what appears to a lot of electrical noise/interference which is affecting various components in the system. This manifests itself as jumpy image on the screen and as static over the speakers (connected to a mountain music card).
If I pull all the cards, I still see the issue with video.
I tried reseating the Video ROM (and busted a bin off the IC, doh!), and once I get the pin repaired and reseated we'll see what happens, but given that the interference seems to manifest across the entire system, I'm thinking the Video ROM isn't really the issue.
Could this be a sign of the Power Supply going bad?
I'm new to the Applle II line, so I'm not familiar with common issues or if this is one.
Thanks,
Jason
There are three items listed here:
http://www.applefritter.com/?q=search/node/Apple%20IIe%20electrical%20interference
Steven
Check the connection on the back of the monitor.
If you have the one I mentioned in this thread then perhaps my fix will work for you.
http://www.applefritter.com/?q=content/fix-a2m6021-monitor-rear-rca-jack
Yes, 2/3 of which have nothing to do with the issue I'm having, hence my question (and the subsequent 3rd search result).
--Jason
Good suggestion! All connections do seem to be secure. Jiggling, cable swaps, etc have no effect.
Also, I'm not 100% convinced it's actually a video issue. As I'm also getting static over the speakers during the time when the image on the screen jumps, I suspect the jumpy video is a symptom, not a problem in it's own right.
Okay, I have two working theories at this point.
I have another //e which I hooked up and found it did not have the video issues, but with the Mountain Music Cards installed, it still had the buzzing over the audio lines.
Some further investigation leads me to believe that there is just really really poor ground isolation going on here.
If I have the //e hooked up to ANYTHING besides mains power, I get the buzz.
With only the video cable plugged in, there is a pretty good buzz.
With only the serial line (to my computer plugged in) less buzz, but still definitely there.
This seems to happen with both of the Apples.
I'm currently doing some investigative work to see if I can determine if there is particular device which is imparting this buzz on my lines (it's all isolated on a UPS...unless it's the UPS).
Also, trying to figure if there some shielding additional grounds I can do somewhere which will help.