AJ6 Zephyr 7701 AM/FM refurbish

I have been trying to get one of these for a while now but whenever they show up on ebay they tend to sell for more than I want to pay.
I got this one off of shopgoodwill for a reasonable price and it was quite grungy but worked with no hum.
The picture above has the contrast out of whack as it was not as dirty as it looks.

It had all its original tubes inside, all marked SEC Hitachi.
Some information I have says that it is made by Sansei, but radiomuseum says it is made by Zephyr in one listing and Sansei in another.

Under the chassis there is not much that needs to be replaced. The square metallic box under the large green capacitor near the volume pot is the rectifier in an unusual mount.

I only found one Electrolytic in the detector circuit and 3 60uf electrolytics in the filter cap.
All of these Japanese AM/FM radios I have worked on have similar circuits and the same filter caps.
I have found that you can replace the 60uf's with 47 or 50uf's with no hum.

I removed the chassis, and the speaker to give it a good bath with simple green.
Re-assembled it.
Polished the plastic and I am listening to it as I type this.
The dial is spot on, it tunes just fine and everything sound great I really like these 1960's Japanese radios they hold their alignment for decades. Many of them sound really good, and the build quality is rather high with zinc plated or gold anodized chassis, in many cases tube retainers, and many of the come with a fuse already installed. I especially like the look of them, they just look totally different than most of the radios that were out at the time, or even later. I like the reverse painted dials especially.

The things I don't like about them are that the plastic often shrinks and or cracks around the screw holes, they suffer from SMD, and the dial covers or face plates are melted in place.



I was working on my 1989 Chevrolet C2500 truck. The temperature gauge was not working and so I figured the temperature sensor needed to be replaced, Since the gauge worked when the gauges all ran through their test when you start the truck. I also notice a small leak where the thermostat is. Today I replaced the thermostat (even though it was fine), replaced the sensor and tested the truck. WTF it still does not work. I also notice I still had a tiny leak and re-tightened the bolts on the thermostat, that's when I noticed a wire that had a connector dangling near something that look kind of like the sending unit I replaced but with a different connector.


There was a second temperature sending unit down by the exhaust, the connector is just clipped on, and had come off. I reconnected it, zip tied it in place, and.... now the temperature gauge works! DOH!


More El Cheapo FM mp3 players

Here are 2 more AM radios I converted to FM/mp3 players.


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:


Datsun Nissan Hitachi A-1561 A-1551 Stereo Car Radio

I picked up one of these at a swap meet recently.

I spent a lot of time trying to find information about this radio on line to no avail. It took me a while to figure out the pinouts of the radio connector.

So you don't have to spend the several hours trying to find it, here are the pinouts.
The metal case is ground for the 12 volt supply.


Multi plug Remote control module from a fan

I had a Pelonis remote controlled fan that I got tired of having to re-oil every year or 2. I was intrigued by the remote control unit, and was curious if it could be re-used in some manner.

Here is the Control Board.

The fan it came out of had a rating of .45 amps. On the board is a 2 amp fuse. 3 LED's that indicate fan speed, and 3 LED's that indicate Timer length, 1, 2, and 4 hours. There is an IR receiver, and 2 buttons, 1 that cycles from off, through 3 speeds then off again, and one that cycles the timer length. A piezo speaker beeps when a button is pressed or it receives the IR signal.

Fan "speed" control works as follows. the Blue wire is common, Grey is low speed, orange is medium, and red is "STR" which I guess means strong? but is high speed.

When low is selected 120 volts is directed through the Grey wire and not the orange and red. Medium puts 120v though the Orange, but not Grey and Red, High puts 120v through Red but not orange or grey.

I decided to build this:

It can switch between 3 1 amp loads.
See it in action: