Electronic Pest Repelling devices do work somewhat on cockroaches because the cockroaches hate the sound they emit and sometimes the sound may be enough to kill the cockroaches.
But sometimes the electronic pest repeller may only spread the cockroaches around the house further.
The best way to get rid of cockroaches it to set cockroach bait poison out, roach motels, roach paste, and even use some Raid Cockroach Spray.
Also using the fogging method of cock roach fogger can help eliminate cockroaches.
If that does not fully get rid of the cockroaches and you have a huge roach infestation it's best to hire an exterminator to get rid of the cockroaches.
The best way to remove roaches from your electronics is to open up the electronics and then kill any living roaches and remove roach eggs.
You can use a vacuum cleaner to suck the roaches out of the inside of the electronics once you open them up.
Setting the electronics out in freezing temperatures can also help kill the roaches and you can wrap the electronics in a plastic bag and then set them out in a hidden place on your porch or in a freezing garage to kill the roaches.
The freezing temperatures will help kill the roaches and the freezing temperatures should not harm the electronics.
Set roach motels and other roach killing bait near the electronics as well and if you have dead roaches in the electronics you can sometimes get the roaches out using some cans of compressed air sprayed into the electronics.
But it's best to open the electronics if possible and physically remove them and make sure no roaches are hidden and even roach eggs can be hidden under circuit boards etc.
If you're moving and the electronics are not all that expensive then it might be best to dispose of the old roach infested electronics and get new ones when you get to your new place to avoid transfer of electronics.
If you have a roach infestation it's best to hire an exterminator to kill the roaches fully.
Roaches are hard to get rid of because the roaches multiply too fast.
Cockroaches do not eat electronics but cockroaches do get into electronics and ruin them.
When cockroaches get into electronics they can short out the electronics circuit boards as they crawl across the circuit boards.
The cockroaches like the warmth and hiding place of the electronics.
You can open the electronics to get rid of the roaches but sometimes the roaches will ruin the electronics sooner than you can get rid of them.
Cockroaches love the inside of electronics to hide because of the warmth they put out and because they provide a great hiding place.
I've had roaches before when I lived in an apartment and they got into my Laptop computer and TV and ruined them both.
The laptop computer was only a few years old and the TV was only 1 year old.
Suddenly they just would not turn on and so I took them apart and found roaches on the circuit boards that caused a short in the circuit boards which ruined the electronics.
I've also had roaches get into a microwave and cause issues with the touch pad.
I did all I could to get rid of the roaches and even fumigated the apartment but still I had issues with roaches because a neighbor in the apartment next door to me had roaches.
You can use dawn dish soap to kill roaches or get some Borax and even roach motels or some of that Raid Roach Killer.