I was just wondering how you bench test a car radio outside a car. I need to test a couple radio's in the morning. I want to use a car battery. Let's here how you do it and is it safe for the radio. Thank you, Bob jerseysky66
From memory.....for the connection part: You should have a red wire to batt.(12V switched, fused), and yellow wire, memory to batt.(12v continuous, fused) and a blue turn-on lead, not needed here (typically routed to amp to tell it to turn on, fused), and a black wire for ground. Also a good idea to ground the chassis of the radio to the neg. side of the battery. With speakers attached, use a cd or tape; otherwise you will need an antenna too. Speakers should typically be 4 ohm. if drivers are not mounted or are out of the enclosure they will have very little bass. Speaker polarity can be checked by using a AA, AAA, C or D battery. With the speaker terminal wires connected to the + and - sides of the battery, if the cone pushes out the terminal identification will match the + and - label on the battery....if the cone goes the other way the terminals will be opposite the battery.
One radio has a couple door speakers already attached. The only free wires are a blue and black wire. Should I run a wire with a fuse from the positive side to the blue wire and a wire from the negitive side with a fuse to the black wire? The other radio has some diffent color wires. I will post a picture tomorrow. Thank you, Bob
Is this a factory stock radio, if so what application? Look to see if there is a female receptacle on the back.
Bob if you want I can come by and show you. Or you can come here. Whichever is good for you. In the 80's I used to do all kind of installs. Out of a flea market. In the parking lot mostly, I made a deal with the guy who used to have a car stereo booth. I made alot of money back in the day.
I want to test the radio's before I list them. They need to go up today. Give me a call this morning when you read this. Thank you, Bob
be sure u know the what the ohm rating for the speakers for each. i would start with 8 ohm. if u use 4 ohm, u could blow the amplifier in the radio.
That is a safe bet. The lower the speaker ohm rating the harder it drives the amp, 10 ohms is quite high so it very low risk. I assume you are only checking to see if it works and not cranking it way up.....
I might only have a 20 amp fuse and could only find one fuse holder. M brother-in-law is stopping over ver soon with some stuff to test them. Here is a picture of the wires. Yellow, Blue, and 2 black wires. [/IMG] This was also hooked up to a cassette player. That is why the wires are the way they are. What should we do? Thank you, Bob
Joe, I will have to catch you later. We were able to get the one radio pictured working. The other one lights up, but I can't get anything :spank: . Of course that was the better radio. Can you help me after the new year? I want to set up a testing area in my garage. I have a bunch of radio'sto test. Let me know. Hope you feel better and talk to you soon. Thank you, Bob
It looks like from the picture, The red spade lug attached to the chassis is your ground or needs to go to the minus (-) of the 12 v battery. The two blacks with the connector are an antenna? The one with the wire nut (Orange in color) confuses me, as there looks to be a blue and yellow wire connected together? It's hard to see where it goes in the pic. So we are still missing connections to the plus side of the battery and two speaker wires to be connected, for one speaker. (Mono) Twenty amps is way too much for an inline fuse! Before anything use a 1 1/2 to 2 amp fuse FOR SURE. As for the ohmage on the speakers you are just seeing if it works and you'll hear something with either 4 ohms, or eight, Etc. With resistance on the output the more you resist or an increase in resistance in (Ohms) or impedence (AC resistance) the more harder the speaker works and more current. It's directly proportional. As the Resisitance increases so does the current. Like wise w/ decreasing the value. Basic Ohms law But it really is miniscule for what you are trying to accomplish. If you get some sound you can assume it is working. Remember if you hooked up a signal generator to the speaker it's AC, just like the output to the speakers which is not to be confused with 12 volts DC on the input. Two different things. I would advise not to just connect 12ydc to the speakers, not a good idea to see cones move, LOL Sorry about those wires I can't see where they go. Thanks, Scott
Oh yea I see that, Everyready rabbit type batteries. Jeeze, Missed that one... Yep you are right, should hear static. Thanks,
