Benchtesting a tape deck..

[180Diablo]

Just wondering if it is possible to bench-test an unknown working radio using a 12v power supply? (Such as one similar to attached image) If not, then how would I go about in supplying power to a stereo to test it outside of the boat?

I would like to see if my deck is a working or non working unit. If it works on the bench, then its a wiring/fuse problem. If it doesn't then I replace the deck with a known good one and see if that works. If it still doesn't work when hooked up, then I know im chasing wires/fuses again.

I currently have an old "Craig" tape deck in my Mariah that doesnt work at all. I do have a ACC/CTSY switch, which the CTSY light in the bow feet area works, but the ACC switch part of it .. well .. I have no idea what that switch is supposed to turn on. Nothing happens radio wise when I flip it down. The switch is brand new. It was replaced about 2-3 weeks ago because the original switch had a broken housing. I wired it exactly like the previous switch (tab for tab).


Second question: Removal. Do you remove any side mounting nut/screws and the mounting screw towards the rear of the unit and then disconnect the connectors and remove the deck? Sounds simple, but I wasnt sure so I figured I would ask.


Thanks .. any help appreciated.

 

[Silvertip]

Re: Benchtesting a tape deck..

Use a battery to power the tape deck. Pull the one out of the boat, out of your lawn tractor, out of your car, or buy two six volt lantern batteries and wire them in series. connect the speakers and fire it up.

 

[180Diablo]

Re: Benchtesting a tape deck..

Use a battery to power the tape deck. Pull the one out of the boat, out of your lawn tractor, out of your car, or buy two six volt lantern batteries and wire them in series. connect the speakers and fire it up.

Hmm so then yes, as long as its 12v it should work. I do have one of those 12v power supplies hanging around the house somewhere, which is why I mentioned it. If I can find it I would like to test it and try and see if I can get the radio working before it goes to sleep for the winter... lol.

thanks for the reply btw

 

[rob711]

Re: Benchtesting a tape deck..

u may have to have the wire for the antenna plugged in to make it work..i learned that when i was younger with a car radio...i did have one work without the antenna

 

[Silvertip]

Re: Benchtesting a tape deck..

As long as the DC power supply is regulated well enough it can certainly be used to power the unit. Over voltage or under voltage will normally activate the protection circuitry in the unit. The antenna does not need to be plugged in to see if the tape deck works. If the tape deck works, then that proves the audio portion of the system works. Obviously to verify the tuner, the antenna would need to be plugged in.

 

[MrBigStuff]

Re: Benchtesting a tape deck..

If you plan to use that table top power supply, check the output current specification against the rating on the deck.

 

[PondTunes]

Re: Benchtesting a tape deck..

Second question: Removal. Do you remove any side mounting nut/screws and the mounting screw towards the rear of the unit and then disconnect the connectors and remove the deck? Sounds simple, but I wasnt sure so I figured I would ask.

Thanks .. any help appreciated.

Radios in boats seem to be done one of three ways.
1) The Cage Approach - Probably the most widespread method is the cage, a metal sleeve that fits over the outside frame of the radio is put into the mounting hole/splash guard and then tabs stamped into the cage's body are bent out to secure the cage in dash. The radio then slides into the cage until some locking tabs "click" into place. Removal of this type usually requires a set of "keys" which are nothing but metal tools that slide down beside the radio disengaging the locking tabs. Wiring can be plugged/unplugged from this setup without removal of the radio (provided you can get to the back of it!)

2) The Pull Out - This radio is installed using a cage that also has a wiring harness attached to it. Sliding the radio in will plug the radio in, these normally don't lock in place. They are designed so that when you get off the boat you grab the handle on the radio and take it with you to prevent theft. These are normally seen in older setups.

3) The Bolt In - Less common is a bolt in radio, these are normally a bit larger in size when compared to a standard din size radio.. The faceplate is enlarged and equipped with holes to screw/bolt your radio into the dash. Once secured a plastic face plate snaps over the screws and conceals them.

4) There is possibly a strap with holes in it hooked to the back of your radio... This backing/support strap is used to stabilize the radio and should help with skipping. If so equipped you will need to remove this strap before you can remove the radio.

 

[180Diablo]

Re: Benchtesting a tape deck..

As long as the DC power supply is regulated well enough it can certainly be used to power the unit. Over voltage or under voltage will normally activate the protection circuitry in the unit. The antenna does not need to be plugged in to see if the tape deck works. If the tape deck works, then that proves the audio portion of the system works. Obviously to verify the tuner, the antenna would need to be plugged in.

Yep thats about all I want to do for the time being, try and isolate if the unit works to begin with. Hopefully its just a dead unit and the wiring is all good.

 

[bruceb58]

Re: Benchtesting a tape deck..

The power supply method will work fine. Just measure the power supply outputs with a voltmeter before you connect it to verify voltage and polarity.

 

[180Diablo]

Re: Benchtesting a tape deck..

Updating an old post of mine ....

I crawled under the dash this past weekend and started looking at the wiring and checked the connectors etc. Noticed an orange wire coming off with a plastic housing that looked like it may hold a cylinder fuse. Couldn't tell if there was one inside or not, so I popped it open and the 3A fuse was snapped.

Went to my marine supply place, got a new fuse, popped it in .. radio works!

So far it looks like it only works when the key is turned into the "run" position. Which is decent, then it wont drain my battery.

 

[Silvertip]

Re: Benchtesting a tape deck..

BAD! If you must have the key in the RUN postion to operate the radio then that means the ignition system is also engergized needlessly and is drawing much more current than the radio.

 

[180Diablo]

Re: Benchtesting a tape deck..

BAD! If you must have the key in the RUN postion to operate the radio then that means the ignition system is also engergized needlessly and is drawing much more current than the radio.

Hmmm, alrighty ... then that is a bad thing..

With the engine off and the key turned, that was the only way I managed to get any sound. I know it wouldn't work when I turned the radio on w/o switching any switches or flipping the key.

I tried flipping the ACC switch and that didn't appear to turn it on. I will do a second attempt using the switch, maybe I didnt turn it up the volume loud enough the first time I tried it.

If that switch doesn't turn the radio on, then I still have no idea what my ACC switch is supposed to run. The ACC switch is new (replaced a month ago) wired exactly how it was wired w/ the old switch. The UP position is CTSY and the lights function. However the lit tip doesnt seem to illuminate. I have tried swapping to a different terminal and still did not light up.

 

[Silvertip]

Re: Benchtesting a tape deck..

Follow the wire(s) from the ACC switch to see what it runs. Then make sure you have +12V going into the switch and out of it when turned on. Connect the radio to the switch and it should work. Of course, whoever wired the boat may have hooked the input to the ACC switch to the RUN position on the ignition switch. Doh -- the key would still need to be in RUN to make the ACC switch work which sort of defeats the purpose of having the ACC switch doesn't it!!!

 

[180Diablo]

Re: Benchtesting a tape deck..

Follow the wire(s) from the ACC switch to see what it runs. Then make sure you have +12V going into the switch and out of it when turned on. Connect the radio to the switch and it should work. Of course, whoever wired the boat may have hooked the input to the ACC switch to the RUN position on the ignition switch. Doh -- the key would still need to be in RUN to make the ACC switch work which sort of defeats the purpose of having the ACC switch doesn't it!!!

Well, another user on a Mariah forum had mentioned to me that there should be an accessory position on the ignition switch itself. When turned CCW there should be another position, which I did not know existed until he mentioned it to me. So I will have to check that this weekend .

I will be checking out the routing from the ACC switch to see where it goes on the ignition switch as you mentioned.

Appreciate all the help btw.

 

[Silvertip]

Re: Benchtesting a tape deck..

If your ignition switch has an accessory position it would likely be in the far left position and you would not be able to remove the key in that position. In other words the ignition switch is just like in your car. ACC-OFF-RUN-START or OFF-ACC-RUN-START. The tip off as to whether you are in RUN or ACC is the gauges and any idiot lights will not be on in the ACC position. If the gauges are active, the switch is in the RUN position.

 

[180Diablo]

Re: Benchtesting a tape deck..

Well I checked and there was no accessory mode on my key cylinder. It would not turn CCW. Off, run and start are the only positions.

Tried to follow the wiring off the key cylinder, but was hard to see where they all lead to (all wiring is wrapped up in a main harness). I wasnt up to pulling down all the tie straps and then having to put them back up before heading home yesterday afternoon.

Same story for the ACC switch.

Needless to say, we were happy to have some kind of tunes when cruising the river yesterday. Although not having an antenna, sometimes the reception would crap out and then come back. But we were ok with that.