El Cheapo AA5 mp3/FM mod

I had purchased several of these FM radio mp3 players:

They run off of 12vdc, and have inputs for SD memory, USB sticks, and possibly even a hard drive. There is also a line in, FM stereo receiver, and stereo out to drive an amp or headphones. Some units have blue tooth capabilities.

I have wanted to add them to a nothing special AA5 radio for a while, but most AA5's don't have a front panel with enough space for one.

Recently I was inventory my small hoard of radios some of which I got when I first started in this hobby, and was buying whatever I could find just to get experience with fixing them. I picked up 3 radios off of ebay for real cheap and saved even more money with local pickup.

The Zenith (with the stain) on the left I parted out for reasons I do not remember, The Motorola is very plain Jane and reminds me of a block of white chocolate, and then there is the Westinghouse.

The "Chassis" (V-2466-x) is used in 17 models, there is a ton of room inside. This one had an option for a clock radio covered by faux wood grain.

My plan is to cut out a hole to mount the player in the middle of the faux wood grain, connect the output of the player in to the audio amp of the radio through a switch, and supply an input for the line in, and possibly an output for headphone. I will also mount a small wall wart inside the radio to power the player and be switched on by the radio. I will use it for a while and then try and sell it.


I Started working on it by removing the chassis and speakers so I could give the plastic a good cleaning.

Inside the case after cleaning.

I had something serendipitous happen when I removed the chassis I found out that the front plate was only partially glued in so I removed it.

 The front plate after some cleaning.

With the front plate off I will be able to cut holes in it a whole lot easier.

I drew up a template in autocad and printed it one to one.

Another serendipitous thing is that the dial pointer/needle had a protective covering that someone may have forgot to remove when it was built. removing it greatly brightened the dial pointer.



I cut the hole out of the face plate with a nibbler and then cutout the plastic with nippers and the nibbler.

here is the player temporarily mounted:

 I rewired the player since I could not find any connectors like the ones it originally came with:

I did some searching and found that the unit will work with anything from 5 to 12 volts. There is a 5 volt regulator right after the +12vdc connection.

I am going to use a 9vdc 700ma wall wart since the unit will need 500ma to power usb devices.

I cut the trace on the board between the 3.3 meg resistor and the pot, I installed a switch between it

Instead of installing a transformer internally, I installed a power socket for a 9vdc wall wart

Here is the back.

 I installed the 3.5mm input jack on the front as the plastic was too thick to do it on the back or side.

It sounds just fine and reception is excellent.

here is more info to help people out:

 

If you want to try this look for the following:
Power switch
voltage regulator (yellow line points to it in pic below)
comes with the wires and connectors.

I have ordered some of these (of different types in the past). Some come with a voltage regulator some do not. I found out the hard way by blowing one up (with no VR) when I accidentally put in too much voltage.

The LM7805 can output 5volts +/- .25vdc 1amp if I am reading the spec sheet correctly it can actually handle up to 35vdc input.

Some of the listings claim it can be used to charge a phone, but one review on a website claims that it will fry your phone, it did not occur to me to use this as a phone charger. I am not sure what the port in the picture above marked "in" and "Charging port" is for since that type of connector is usually used to connect a device to a computer. I am hesitant to plug something in to it.

The unit will scan and store all stations it can pickup to saved presets, it has very high gain for such a little radio. There is an EQ function which seems to only be for mp3's and not the radio. It has a clock but I cannot figure out how to set it. I have not found a manual for it so far. It has a small amp built in that puts out about 1 volt max so a preamp is needed for some applications, the 12av6 worked fine for that. There is a built in volume control as well. Thankfully the boards are marked or else it would be very difficult to hook these up properly.

Sound output in this radio is ok considering the type of speakers, when I tested it with a 200mw amp and nice 8ohm speakers it sound just as good as any small stereo you could have.

The remotes for these are all the same except that the buttons may be marked different, I have 2 different units and the remotes work on either one, but on one the EQ button is scan up, pressing it does a scan up on this unit. other buttons labeled differently operate the unit the same as my other one with different markings.

The radio is a Westinghouse cr-510. Good luck finding one.

other models:
cr-500
cr-501
cr-515
cr-520
cr-521
cr-530
cr-531
cr-535
cr-536
h-200t5
h-201t5
h-205L5
h-210L5
h-211L5
h-215L5
h-216L5