Monochrome LCD repair

[RLBennett]

I have a Tektronix o'scope and two icom ic706 transceivers with failing displays. Started as a dark spot in the center and has spread out to about 90% of the display(s). Has anybody tried to fix a problem like this? Perhaps compressing the displays in a low temp oven? Replacement displays are not available for the 706 radios and the scope display is really spendy. Seems like the display is delaminating from the high temps here in SoFla. The displays were not folded, spindled or otherwise mutilated, just too much heat for too long. Any advice?
Thanks!

[tautech]

What model Tek?

[wraper]

Unfortunately you cannot do much other than discarding such LCDs.

[RLBennett]

The scope is a THS-710A.
I refuse to make the failed LCD refuse, at least without trying something even it is wrong. Wish I could just refuse it with a new fuse. (Ain't English just great?) I am sure that the displays are not ruptured. How in Sam Hill are LCD displays assembled anyhow?
Squirt some juice between two sheets of glass with some other stuff, compress and heat? Seems like the displays have de-laminated. Maybe I can interface an old computer lcd? Thoughts?
Tnx

[Rasz]

there are three way to go about it

1 find original part number, buy replacement
2 find a generic replacement
3 reverse engineer pinout/protocol, emulate it

https://www.eevblog.com/forum/testgear/tek-ths720a-portable-scope-teardowndiscussion/

tek seems to be using 320x240 standard old school STN/DSTN lcd with buildin controller, plenty of those on the market, you need to  open the scope, take it out and identify the model/make or at least size and pinout
example
http://www.ebay.com/itm/5-7-inch-STN-320-240-LCD-Display-SHARP-For-LM32019T-Panel-Free-Ship-/321240493950
http://www.panelook.com/LM4Q30TA_SHARP_4.7_LCM_overview_17365.html

as for the icom - you brought that one on yourself by supporting corporation that doesnt give a single shit about HAMs, proprietary digital codecs (ambe), proprietary displays, if you are retired with a lot of free free time you could painstakingly reverse engineer protocol this lcd uses (if it has build in controller) and recreate it using microcontroller/fpga+generic graphical lcd combo, good luck :/

[RLBennett]

Rasz
Thanks for your reply. I have found a display for the scope, Sharp LM32P010. Priced from $225 to $300 from reliable suppliers and some cheaper but I don't trust the seller(s) for the cheaper units. I will probably have to bite the bullet and buy a new one from a reliable seller. Or, perhaps for a few more bucks, maybe a different scope.
As far as the Icom, you summed it up correctly with their GAS factor and not only with the amateur radio equipment. It was about the same piss poor attitude with their other products and support. However, I did not buy either of the radios. One was a gift from my wife in 92 or 93. I sent it back to Icom for warranty service and they could not or would not troubleshoot and fix it. Came back with the same problem that I fixed, a bad PLL chip. Had to do go through most of alignment  after replacing the chip.. The other radio belonged to my father before he passed away. Thing is though, that was the only radio that did what it did back then..
You can bet the next transceiver I beg my wife to buy me..... I mean that I buy without her knowing....woops..I mean that I purchase will not be an Icom!
Just an aside, the display was made by DLC Display Company. I emailed them three time for a data sheet or a replacement. After 3 months, not a peep from them. Maybe taking support lessons from icom?
Ok Rasz, thanks for the encouragement and reinforcement of my feelings for icom.

73
Rob


Sent from my iPad using Tapatalk

[Rasz]

LM32P010 lists at ~$90 on ebay (including shipping) from good chinese sellers with fast shipping, I would start there.

as for icoms, good and bad (and good again) news.

good:
-someone already did all the steps I described for similar model radio (reverse engineering controller, replacing with modern one), so that proves its doable

bad:
-it was $300 for the kit
-its discontinued
-it was a different display anyway

http://forums.qrz.com/showthread.php?302777-IC-756-Display-Replacment
http://www.pa7fa.nl/PA7FA/Introduction.html



Now I did some digging, found service manual, lcd is controlled by dedicated microcontroller with buildin LCD driver + additional SED1522
http://www.orientdisplay.com/pdf/SED1520.pdf
sed alone is not enough to drive such busy lcd, bottom alphanumeric row alone is 490 pixels

looking at diagram
HD6433834A4IH does 4 column x 31 segments = 124pixels
SED1522 does 8 columns x 69 segments = 552pixels

This is a problem, its 'easy' to replace SED driver, you just cut 12 traces (8 data + control logic), plug micro into those lines, plug
http://www.ebay.com/itm/ILI9325-2-4-TFT-LCD-Module-Touch-Panel-240-x-320-Dots-37pins-8-16bit-/181597351507
into the micro and you are done.
Sadly HD6433834A4IH (no idea what microcontroller tha is, and even if I knew there is no way to get firmware) is not that easy tho, only way to display what it displays is to sniff serial traffic from the radio.

Here is where I hit the jackpot:
http://www.oz9aec.net/index.php/ic-706/498-diy-remote-kit-for-the-ic-706-part-1-proof-of-concept
http://k9so.net/files/shifter.pdf



This YT clip is enough to emulate whole Head display for this radio . All the information needed is there, serial data send from the radio to the head and Head screen at the same time = BRILLIAND clip. Alexandru Csete is the man!

You can reimplement it with smallest $3 Arduino and $5 LCD. Microcontroller will passively listen on the HEAD RX line to the data from the radio. Every time it receives data packets it updates LCD.

This is a great beginner project if you never programmed microcontrollers. Should take you couple of weeks of leisure learning.

[RLBennett]

Rasz,
Thanks for the very useful info. I will look at the OZ9AEC & K9SO stuff. I can make it work, me thinks.
Thanks again!
Rob

[RLBennett]

Rasz,
I just poked around the OZ9AEC web page. WOW! Lots of great projects and info. Thanks again for turning me on to his website!
I wonder if I can use an old IPhone or other device to interface the 706. The IPhone has an RS232 interface but have not looked at the protocol of the port. Also would have to build an app to make it work.
Hey, thanks again for the wonderful info!
Rob

[Rasz]

dont know about iphones, but judging by proprietary connector its going to cost >$40 for cable alone, + no idea about writing and loading own software on this platform

might be easier, cheaper and more comfortable to use of of those cheap bluetooth modules (2.4GHz so shouldnt interfere with the radio), its small enough it should fit in there
http://www.banggood.com/HC-06-Wireless-Bluetooth-Transceiver-RF-Main-Module-Serial-For-Arduino-p-80364.html

sending "AT+BAUD5" will permanently set this module to operate as a serial bridge at 19200 speed, same as icom
solder RX pin to the RX pin in the icom head, connect with phone/computer and you will receive same serial traffic head unit receives, rest is up to your coding skills

[RLBennett]

Rasz,
That looks like a great idea! I looked at the module and looks cheap nuff even it does not work. As far as coding goes, don't think I ever written any... Nope, never written code. Guess it opens an oportunity to learn something new.
Rasz, been in the radio and electronics stuff since the mid 70s so I guess you could say I'm a bit " Old School". Cut my teeth on tube type stuff, TVs and radios, analog of course. Guess it is time for this old dog to learn new tricks.
Thanks for the passel of great ideas and info!
Rob

[Rasz]

you can start by obtaining either
-usb to 5V serial cable
or
-rs232 to 5v serial converter (max232)

or reusing radio programming cable if you have one (usb/rs232 on one end and 3.5 mm jack on the other)

you will also need ethernet cable and ethernet socket to recreate http://www.remoterig.com/schema/ICOM-706%20cable-cat5-1a.pdf and tap LTXD line using your serial cable

scratch that, icom uses OPC-581, not 8p8c connectors
http://www.remoterig.com/wp/?page_id=444#tabs-2
instead of buying $50 cable just tap LTXD inside open panel

at this point you should be able to receive icom traffic in a terminal window on your computer, only after this point we can start worrying about coding anything

[timb]

Just FYI, the iPhone doesn't have an RS-232 or any other useable wired serial interface. The Bluetooth 2.1EDR stack doesn't have SPP support either, so that's s no go. You'd have to JailBreak it and replace the BT stack, or just use an Android. Honestly, you'd be better off with a micro and LCD at that point.


Sent from my Tablet

[RLBennett]

Timb,
Thanks for your advice. Perhaps I was thinking of another I-Device that supports a serial port. I would swear that I saw a pinout that showed a serial port either on a docking device but probably it was for a different IDevice. Hmmmm.
Anyhow, thanks all the same.