Yupiteru MVT-7300 lcd repair

[aprilexe]

The lcd on the MVT-7300 fades after about an hour. The light brightness is fine, only the lcd characters dimming. Holding at a near flat angle helps. I haven’t tried adding polarizing film yet and I’d prefer to find a replacement or compatible. Best case there is a capacitor that needs replaced ?

 

[markclark]

The lcd on the MVT-7300 fades after about an hour. The light brightness is fine, only the lcd characters dimming. Holding at a near flat angle helps. I haven’t tried adding polarizing film yet and I’d prefer to find a replacement or compatible. Best case there is a capacitor that needs replaced ?

Take it apart and identify the display manufacturer and part/model number. The display may be a complete module. Search google with the part number and see if you can find the part. Otherwise, you need to determine the part specifications and find a suitable replacement display.

It is possible you only need a sheet of luminous LED for backlighting. You won't know until you take the unit apart and examine the display construction. You should try to get the service manual and a parts list - search the web. Good luck!

 

[merlin]

Many of these types of displays have a line that sets the contrast.
Probably not adjustable on your radio so contast sometimes fades with heat.
This is usually due to a failing resistor changing value.
Let me dig up the manual for your radio and see if this means just replacing a resistor or the entire display module.

 

[merlin]

Like many other radio manufactures, there just doesn't seem to be any schematics or service manuals in the wild.
I was looking at buying one of these anyway,, so when acquired, I will dig into it and see what gives with the display.

 

[aprilexe]

Thanks Mark and Merlin. Here’s the schematic I managed to find a while back. The part number didn’t show any results searching. I still haven’t done the full tear down so we’ll see.

Merlin if you’re looking for a 7300 there are a few on eBay listed from Japan. Receiver wise it’s not quite as sensitive as my MVT-7100 but the narrow AM filter is nicer on hf.

 

[merlin]

Thanks aprilexe.
I saw a few listings for the 7300 on ebay. My priority right now is the makings for a desk computer to replace my Dell inspiron. (I let too much smoke out of it)
It took some ferreting in old drives, but found service manuals/schematics etc. for the 7100 and 7300. Really didn't know I had all that.
Soon as I can upgrade my Mega account, I'll host them for you.
Cheers

 

[markclark]

Thanks Mark and Merlin. Here’s the schematic I managed to find a while back. The part number didn’t show any results searching. I still haven’t done the full tear down so we’ll see.

Merlin if you’re looking for a 7300 there are a few on eBay listed from Japan. Receiver wise it’s not quite as sensitive as my MVT-7100 but the narrow AM filter is nicer on hf.

The numbers adjacent to the LED on the schematic may be part or manufacturer identifications. I can't clearly read the numbers or letters. try to Google the numbers; you'd be surprised what comes up.