Batboard

My IFR COM 120B has been working great for years until today. I turned it on and noticed that there was no spectrum analyzer or scope on the display.
I could not use the tracking generator so I checked the clock/calender and the date and time was erratic. I set the date and time but when I turn off and turn on the monitor, the date and time was erratic again.
I ran a diagnostic and it shows a "Real Time Clock Fail", everything else passed.
Any input on how to correct this problem will be most appreciated.

Thanks,
Marshall
N6RTR

The RTC module has a built in battery, which has probably died. That kills the options storage, so the unit forgets it's serial number and installed options. It's tricky to replace, as the modules aren't being built anymore - I've heard of people carefully cutting the top off and replacing the battery.

The RTC modules are still available but will need to be programmed.

Normally I do the NVRAM battery and RTC modules on the controller / Up Board.

Thanks for the information. Where may I find a place that has the modules? I am in the Southern California area. Would you know of a place where I may order a module, or a repair shop or would it be easier just to replace the NVRAM battery myself? Sounds like I may need the calibration code in order to reprogram the options back into the monitor. I don't have a clue what the calibration code is and it looks like I may need to take it in to a shop to be repaired.

I remeber some people said COM120 series option status and calibration data storaged both in NVRAM and eeprom in front panel CPU.I tried to replaced battery in COM120B,first power on it showed "loading ????? in front panel",and options no changed.But I'm not sure there is another battery in DS???? NVARM chip,or only one on CPU board.

No, the options are NOT stored on the front panel, only the calibration settings (upon reflection, I wish I had stored a copy of the options structure on the front panel, and in the flash file system, but oh well).

PM sent

So if we lost battery on 120A/B,we will lost all options set?How should we do if it happens.

The battery is internal to the RTC module.

The NVRAM battery is separate on the processor/controller and may cause the loss of some settings and files ...cal will be copied back from the flash as was mentioned before.
One way to tell if you have a dead NVRAM is getting the message about restoring calibration from front panel during power on.

When the RTC battery goes you usually fail the power on self test and the options typically go as well.

So did anyone come up with a replacement part for the DS1286 on the controller Bd for the Com120B.
I see some other RTC modules in Mouser. These Dallas chips are prone to fail due to age. I have
changed many of them in other equipment.
Johnny S.

Com-120B also real time clock fail, all options gone.
Changed clock module, pass all tests, still no options.
Obtained option codes from Aeroflex, entered numerous times, still
no options installed.
Any suggestions appreciated

Chris
gmrsinc
tracomm@yahoo.com

You need to have the serial # set before the options numbers will take - otherwise the serial # embedded into the options won't match the unit's, and it won't be accepted.

Since the 120 is now well and truly out of support, give me a bit to verify my memory, and I'll give you the commands to reset the serial number. You'll need a serial terminal on the unit (or, I suppose, you could use GPIB).

Thanks for the information, your assessment certainly makes sense.
Any info to reset the SN# would be greatly appreciated.

I've posted some info over the the Aeroflex questions thread.

http://www.ebay.com/itm/1pcs-DS1286-128 ... 1363982582
DS1286 1286 DALLAS WATCHDOG TIMEKEEPER SRAM DIP-28
I bought two of these for about $8 ea.
Problem solved. Clock OK now & Spectrum Analyzer OK.
I did put in a socket. This was a Bear to get out without damaging the board.
Holes a tad bit small.
Johnny

My COM120b clock still keeps good time. It gets a fair amount of use. When not in use, it is usually plugged into AC on the bench. I wonder if leaving the COM120 plugged into AC would help preserve the battery in the Dallas clock?
Ken

keeping it just plugged in by itself will not help.

Maybe if you left it turned on but then you have a worse problem of the screen burning in.

The RTC has to be programmed to the unit so just replacing is not enough. It should get it past the self test though even un-programmed.

Hi all.
Excuse for my bad English, I hope you'll understand me.

In my COM120B just died back-up battery in RTTC timer, and I lost irrecoverably all my highly-valued options. Therefore I try to warn all IFR COM120 owners, as a precaution my sad end..
All IFR COM120-B instruments are in danger - irrecoverably loss of all options is unstoppably approaching. Unfortunately, loss of options is unsolvable accident for most of us..
Here are my observations, experiences and tips to prevention of accident. I hope that will help you.
Our popular IFR120 contains Real Time Clock - Watchdog Timekeeper Dallas DS1286, located on the board "Controller tray".
Dallas DS1286 contains a timer, RAM, 3V lithium battery backup for RAM and 32kHz crystal encapsulated in one plastic black box. There are impotand information stored in the RAM relating to the instaled options, state of operating hours and so on. Discharged internal backup battery means you can lose all data from memory. The instrument usually displays "System failure, Real Time Clock is bad“. It seems easy to solve - You buy cheaply on ebay new timer DS1286 and you'll think, it's ok. Unfortunately, it's not a win, especially when you had options installed. There are a two problems:
1)If you had options, you lost them (new DS1286 timer has not the correct contents of memory)
2)All DS 1286 timers are very old today, although purchased as „new“. Production of this timers ended in about 2007. China has warehouses full of these old circuits, so on ebay is many offers. So even „new and unused“, it is old circuit produced about 10 years before. So contains a battery which is about 10 years old. The battery is permanently discharged from the moment of manufacture. The manufacturer guarantees 10 years without voltage = today you can not buy a timer with fresh batteries = death of battery are approaching. May come today, tomorrow or in five months, but it surely will come. Infrequent use of the instrument = sooner death (internal backup battery in the timer is automatically disconnected once device is on the Ucc). But permanent running of the instrument is unreasonable solutions.

What is the solution?
1)Absolute matter of priority - read the contents of memory in the timer DS1286 and save it. Once you have saved the contents of your memory, we won. Any possible problem with timer will not destroy our valuable options from now. You must extract timer from the board. I recommend preheating the board, but be careful - internal battery does not exceed +85 st C. Beware - on the board is still second big Inorganic Lithium Battery 3,6V - I do not know what backups, but is clear - on board will be an additional circuit(s) under voltage from this big backup batt. So beware of random interconnections or short connections during handling. After extraction I recommend to put the socket for DS1286.
2)Now is time to solve the battery problem - only way to do it - carefully grind the plastic housing up to the internal battery, disconnect from timer and connect it to fresh external 3V Lithium battery (+batt to pin 25, -batt to pin 21).

The operation is demanding on accuracy, it is necessary to have small engraving milling machine.
I did everything to easier it for you. I do not take any responsibility for your failures or accidents with this solution.
When you succeed this operation, you never need to solve the problem with the DS1286 or loss of your options.

If anyone knows how to backup data from RAM in DS1286 without extraction from the board, please give info.
Good luck!

Hello everyone ,

when all else fails try Fourms . Thats where im at since finding out Aeroflex was bought by Cobham , no more support for my Com 120B
I have lost All options , Possible RTC failure but date , time OK, system passes all tests , even RTC
if iv had a RTC failure and lost options am i screwed Now? i had almost every option installed except i think 3 of them .
can i repair the loss of options by any means else ? or is there some other failure that happened .
when i go into spcl button mode it shows everything still , but when i execute them it says NOT INSTALLED
going into version menu only shows the options which are hardware options , not my software options
i got my quote from custom cal a few months ago planning on replacing battery in RTC . i should have done it last month . Murphys Law i guess

PLEASE any help very much appreciated , here is my info on unit
Com 120b Serial # 500009822
Options Tag 003040507111213141516

also here are some photos
https://drive.google.com/open?id=0B0u9J ... np5NTRBMTQ
https://drive.google.com/open?id=0B0u9J ... ENoY29EVG8
https://drive.google.com/open?id=0B0u9J ... DFvVGVwN3c

update , the clock does not keep time. stands still after shut down. date as well . so RTC has failed . so even with a new battery installed i wont be able to reinstall all the lost options ? does anyone know if Custom-Cal can get the options back or another service center that could. i have never ran into a issue like this before. but with equipment that's 15yrs old its always a possibility , i have tried resetting factory defaults in the system menu no prevail. should the start up screen show initializing then system test every time , cant remember
any information appreciated ,
Keith N

I'm in the same boat. I lost my RTC too, and options. Replaced the RTC, and my Options are blank, but at least it's passing all tests and not failing the rtc test now, and keeping time. Any help to get the options re installed would be great. My serial is 50010357.

So according to maxim integrated the DS1511 is a replacement to the DS1286 according to them the only difference is the DS1511 does not count down to the hundredth of a second, Not sure if this would make a problem but it may be a replacement option, I am sure JRY or Wowbagger could chime in as to weather this would be an issue. hope this is a good option.
John

looking briefly at the Maxim site the DS1511 is equivalent but not a direct replacement. Didn;t really look much further but that implies it would be an effort to switch to that device.

Would just source the DS1286 vintages as long as they are around. lot''s of vendors will carry obsolete chips for just these support issues.

Of course the problem is on this device the shelf life of the battery is limited so literally the clock is running on the parts on the shelf. It's a looong life but it's still and issue to be aware of.

well the com120b i had was not fixable in my situation (second hand purchase) . but like a great one once said " all machines eventually fail " i understand age of components but man what a BAD place to store $$$$$options$$$$$ in volatile memory. they tried a few cards from parts units , but with no luck of having any options . and the few options that where still showing in my unit where gone on the other units card. the options where the hardware installed ones. second af gen, RF amp they disappeared.probable issues with the SN not matching or no options where on those cards. it was a very strange failure, lost half of the options and the others still showed. the clock wouldn't keep time or date. was a RTC failure but didn't see one fail like this , from what people have said. to you other guys out there , maybe start a new thread , people don't always check these old ones<<<<<<
Best of luck

OK, everybody, from the top:
1) I will help who I can, when I can. The most assured way you can get me to put you last on my to-do list is to keep pestering me by IM.
2) I need your serial number, the options you had (don't give me every option - I don't take well to being snowjobbed). Either give the options BY NAME, or better still, give me the output of the *opt? command before you lost your options.
3) Tell me what RX IF filters you have installed, esp. if you have the second optional filter.

If you have a COM-120 and your RTC hasn't died yet: RUN THESE COMMANDS RIGHT NOW!
*opt?
*idn?

and save the output. That tells me what I need to know.

Last: If you are having other problems with your COM-120 - please, don't ask them on to me by IM, ask them ON THE FORUM.

I started my unit up after 3 years and looks like I'm good, but I plan on changing the battery (parallel a new one) on the chip.
Took photos of my active options and ran a few tests. In case it will fail so I can get them back.

Wowbagger , when you say
"RUN THESE COMMANDS RIGHT NOW!
*opt?
*idn?"
do you mean by GPIB, by serial? What's the procedure to run the commands? Sorry, never hooked up anything to the unit other than a coax cable.

One more question. The Dallas chip is on the "controller board" which is the number X from the front panel?

Thank you!

Hook a serial cable from the RS-232 port on the instrument to a serial port on your computer - either a built-in or a USB to serial adapter. Set up a terminal program - Procom, Windows's terminal program, Minicom, whatever. Set the terminal program to the same settings as under the "Settings->Serial" page of the COM-120. Make sure echo is ON on the 120. You should be able to hit return a couple of times and get an "!" for a prompt.

I have used the procedure to replace the RTC chip battery on my friend's COM 120B. He says he is still getting the "Real Time clock fail" message..... I assume something needs to be done to reinitialize it, and I also need to know how to reset the options. The "Options Installed" sticker says "O0010812" & S/N is 500009442 . Can send pics of stickers if desired. When/if you give me the info, does it need to go in via the serial port or can it be done with front panel keyboard? Thanks in advance for any assistance you are able to give!
William Thrush, P.E. N7MLL for Jack Williams W7HNH
bigdaddy@superxstudios.com

I have the same problem with 2 x IFR-1600S units, clocks stopped updating and are about to lose their S/N & option bytes as the battery gets flatter...

Hi Wowbagger,

Today I was able to remove the tray and replace the battery by the means of drilling my way to the pads and soldering a new one on top of the potted battery that had only 0.4Volts left. Although I was super careful, the options are now lost, the run time shows a bogus number but the replacement succeeded.

I would like to ask you for help to restore my lost options. Everything required is here : https://goo.gl/iXBBmm
Images were taken before attempting anything.

Please help!

Thank you!

Raz

Is Wowbagger responding to anyone?

I've been on a week's vacation, and will need some time to get caught back up.

Wowbagger, any chance you could help?
Thanks

I am in the same situation, my RTC failed, the options lost, I replaced the RTC module, now the clock runs, the run time has a bogus number, still no options. Any help from Wowbagger or anyone is greatly appreciated in restoring the options. If needed I can email images of the serial number and options tag on the rear of the IFR, our IFR has many options, the ones used the most are the Tracking Generator and LTR Trunking. The option tag reads 01020304050711121314. I tried the *opt? and *ibn? before I changed the RTC, the options showed 0, and the idn showed: IFR Inc. COM-120B,0,0419-0410-0415-0301. If that's any help.