Well, my Sanyo M-X720K finally arrived on Wednesday. The shipping box contained lots of styrofoam peanuts! I dug around for the boombox and pulled it out. It was wrapped in only a couple of layers of mini-bubblewrap. Uh oh. I gave it a visual inspection and everything seemed to be okay - no missing parts, no cracks, and no big chunks of plastic missing.

When I finally got around to plugging it in to listen to it, it had no power at all. I worked the switches thinking the power switch could be dirty. Still nothing. Oh, no!

I opened the M-X720 and something small fell from the bottom as I pulled the case apart. When I saw the familiar brown, dark green, and light green colors, I knew it wasn't good. It turned out that part of the transformer PCB had broken off.





I pulled out my trusty fine-grain, modeling sandpaper and sanded the ends of the traces so I could bridge the gaps. Then, I applied some Gorilla glue to the PCB pieces carefully with a toothpick. After the glue set up firmly, I then soldered the gaps to complete the connection. It's not pretty, but it gets the job done.



It started receiving power, but I noticed that the VU meter showed it was well low. A DC power adapter was plugged in and the VU meter went higher. Darn! Something was still wrong with the AC power. After a lot of metering and tinkering, I narrowed the problem to the voltage selector switch - a few shots of DeOxit and working the switch cleared things up. Alright!! Now we've got full power. The solder bridge worked!

Time to concentrate on cleaning now. It became painfully obvious that whoever the previous owners were did not fully appreciate this box. Hundreds of very tiny, white paint specks were all over the top and there was some red paint marks below the tape controls. Inside, the box was filthy. Here's an example:



After a good interior cleaning, I snapped a shot of the heatsink. None of my other boxes have one quite like this. I think it's cool!



Moving on to the cassette, I noticed that one of the screw posts had snapped previously. Had someone else been inside this box?



A little Testors model cement and a couple of hours and that baby is not going anywhere.

Here's a shot of the primary electronics - thankfully it all comes out in one piece!



Cassette motor:



The Sanyo M-X720K only needs three belts - flywheel, spindle, and tape counter. Figuring out how to get to them was a nice puzzle, but the actual changing of the belts was fairly easy.





Here's a shot of the front casing:



Oh, the switches and knobs were the absolute filthiest I have ever seen on a boombox. Each switch required at least three separate treatments of DeOxit. The MONO/STEREO/WIDE needed six!!

Alright, so now we have power, the inside is clean, the cassette has been cleaned, demagnetized, belted, and head adjusted, and switches cleaned. Time to reassemble!





It appears that everything is working! YAY! Still needed to work some of the switches to remove that last bit of static though. I carefully removed as many paint specks as I could and then pulled out my trusty toothbrush and Orange Glo for the final detail.

It still has a couple of discolored spots on the left grille. I'll be drybrushing the grilles later.

I can't believe I finally have a Sanyo M-X720K. I first saw a picture of this boombox a long time ago and it was love at first sight.






I still haven't had a chance to really listen to it yet. The girls are still in bed this morning.

So, wait a couple of hours before asking.

Simply beautiful Fatdog!You have great taste in everything all around it seems!I have a 720 that my service guy doesn't seem to want to work on.I wish I had your tenacity,skill,(?).

When I saw your "new puppy" reference,I was thinking of a dog.I'm wanting a dog actually and was very excited to read your post.Now I've totally forgotten about wanting that dog I just wish I could get my 720 running.

nice box FD...

good job and nice find....these things are so old an brittle....it sucks but at least you saved it from the junk pile!

Thanks, guys!

Jovie, dude! You need to get your M-X720 back in action. I finally got a chance to really crank this thing and listen to it. Wow!

The 2.5 ohm (8W nominal) speakers can put out some seriously nice sound. Unfortunately, they are not 8" speakers like one is led to believe from the grille diameter. The speakers are closer to 5" or 5.5" - bummer.

If this boombox had a LOUDNESS feature it might be able to take on my Rising head to head. The Sanyo definitely has a better sound than the Sharp GF-9494X. I'd say it's as smooth as an M70, but definitely not as powerful.

A few observations:

1. Speakers are smaller than they appear
2. This box is heavy for its size
3. The tuner is unbelievable
4. It has no LOUDNESS switch
5. Dolby NR is a nice touch
6. Weighted tuning dial
7. In radio mode, the left VU displays power - the right VU displays signal strength
8. Blows my Sanyo M-9935K out of the water

Oooooooooo, what a story! I don't think any of the flaws were covered in the listing - like paint, and such?
Do you happen to have Sanyo 920 by chance? It would be interesting to hear how 720 and 920 compare

That's right, Vladi. None of the flaws were listed at all. Thankfully it all worked out okay.

Nope, I don't have a 920, but I'd love to hear one.

One thing I forgot to mention...

I found what appeared to be the original sticker residue from the speaker label underneath the right speaker. Of course, you know me, my mind started racing with ideas.

Does anyone have a picture of the original M-X720K boombox label??????

Great post (storytime with FD!), and really happy for you to get the results at the end of it. PLUS as usual there are techniques and ideas in your story that will benefit others.

Three cheers for Fatdog..

very nice

Yeah, it´s a very pretty box now.
Thanks for the interesting story.
Hope you enjoy your new "puppy"!
Let´s make some noise.

Good to see you got her going again!

I've liked that Sanyo model ever since I saw that JDenver chick sell one on eBay.

Congratulations!

One gorgeous box, Fatdog! I can't understand why people would abuse something like this.

The M-X720 looks about the same size as a Sharp GF-9000. What are the dimensions in inches?

Great repair on the broken board!

Thanks for sharing this awesome restoration.

nice win-- great fix --fabulous box.

there is also a quality competitor to the 720 -

the jvc m50 is very similar in size, shape, design and in overall look --and they often go for similar $$.

well - once upon a time

i had them both here --and on a side-by-side comparo --
the 720 looked far more elegant --and its sound was alot more smooth --

swell story, all around for you fatdog !

fantastic work bobby, great box to, your a man after my own heart, fixing boxes on the kitchen table

Nice choice FD! It has all the right classic styling cues, thats class.

Wow Bobby! That's a great play by play picture story I can see how you've fallen for this beautiful looking box. It's very attractive. Judging by the chrome speake cap size, I thought they were 8" woofers.

nice new puppy dawg

she looks gorgeous bobby!definately worth all the work and glad to hear it worked out good!

thanks for sharing the repair-job & clean-up

Congratulations Bobby! Looks like that lost dog's found a great new home.

Brilliant restoration story and end result.

Rock On Brother!

nice work man, thanks for sharing.

beauty

Love those close up pictures FD very good!

Congrats on giving her that TLC she needed she looks just stunning.

Thats a real Beauty Bobby,congrats! I'm glad you were able to fix the nasties up.

it's cooling box~~~

Hi FD-Nice surgery!! I'm impressed.
I really like the looks of this one.
Older Sanyo's are classy boxes.
I want a M9980 I think that's the one.
Really nice Sanyo FD
-Have a great weekend-Ghettoboom777.

Well, guys, I got to see it and hear it in person this past Friday. Photos don't do it justice...and the sound rates a definite WOW!

My gosh you guys who work at NASA or something really make working on these things look easy!!!

I love the detail photos and the story Bro!

Great looking box too!

Question on the side: Did you ever repop grille stickers for the GF-9494?

Great score Fatdog and excellent repair.
The M-X720 is one of the hottest looking BBXs ever!

Thanks for all the great comments guys and gals.

fatdog -- you must be wall-to-wall smiles right now --as you did get a 'jewel' box.

That's an awesome box...i'd love to find one just like it

-gsbadbmr

Ah. This brings back memories. I had one, but, traded it with fuzzyduck foa 9994. Great sounding machine.

Excellent, really really excellent.

Nice look BBX , and fine job !!