AOR AR-3000A failure

[csialv]

Hello friends, I have a AOR AR-3000A since 1992 that never gave me any problems.

Since a few weeks ago, randomly, turns off and after only two seconds back on.

The first was to change the internal backup battery CR2032 and also changes 2200uF/16V electrolytic capacitor installed between the pin power connector, for loss of electrolyte.
I tried two different power sources but the input voltage never fails. Measuring with an ammeter, when the fault does, not increase consumption as is possible short of some components.

These repairs did not erase the damage. Sometimes it is working days and does not fail and sometimes you do constantly.

I have checked connections and I have re-soldered pins that were in poor condition (78M05, L780S09) and changed another condenser suspect(C156).

The power source involves three integrated circuits: IC-11 (L780S09 that provides +9 V), IC-10 (S-81250HG that provides +5 V to power the digital section) and IC-12 (S-8054HN, a detector voltage). The output of +5V in IC-10 never fails. The +9 signal from IC-11 crash, but due to lack of strobe signal on pin 4, and +5V from IC-9 also fails both as a result of the failure in the digital section. But what came first? Is the chicken or the egg?

Fails first power source and therefore cut the IC-11 +9 V and IC-9 cascade? or failed the digital signal sent to IC-11 strobe?

Has been tested to detect fails in components due to heat, by heating with a soldering iron or frozen with dry air-cooled, with no results.

I can send for repair service because I suspect it may be days or weeks without fail

Any idea?

Anything similar failure?

Thanks in advance

 

[n2pqq]

Just a quick idea > maybe try a different CR2032 battery. Who knows just by chance it might be bad.

 

[csialv]

Thanks, but I already tried that option. I've even tried applying voltage on the circuit from external sources ...

 

[Rui]

AR-3000a

Aor 3000a

I have almost the same problem can any help

Good day to all, (new member)

I am new at this, but please help.

I have an aor 3000a, when I switch on the scanner nothing happens (no power); I have change the battery cr2032, and the transformer 12v/ 14 v ,but still nothing, I check the fuse (its ok), I have reset the scanner nothing.
What should I test for first e.g. the 2200uf/16v electrolytic cap or the ic L780S09 ?
Any ideas?

Thank you

 

[csialv]

Hello, first make sure that the correct voltage between pin's of capacitor 2200uF/16V is correct. If it does not arrive or there is short circuit proof to disconnect the capacitor and try again.

Then test the input pin 1 of IC-11 (L78S09). Measurements must be equal to that in the condenser ends. Then measured their output, which is pin 5. There should be +9 V. If they are not measuring the voltage at pin 4 (Strobe) and if still no boot test bridge mass.

In IC-10 (S-81250HG), regardless of IC-11 must have the voltage at its input and +5 V at its output. Go and check everything.


You can write to my private mail at csialv @ yahoo dot es

Sorry for my bad english...

 

[nav-tv]

Guys, I'll be glad to help you diagnose your problems. I have a working 3000A and could take scope and voltage measurements at key components for you so we could compare our readings. I suspect a problem with the Font panel (digital section), at least that was the case with my 3000 (not A).

Let me know if you need help !

 

[Rui]

Aor 3000A

Hi there,
My name is Rui, I live in south Africa my English is not to good as well.

I have not checked anything yet! but I will,... but thank you very very much for your reply


Thank again and I will came back to you for your wonderful help , if that's is ok?

regards\Rui...

Csialv is this the way you write your email?

csialv@yahoo.es

And for the other member thanks you too any help will do .. there no aor repair company here in south africa

 

[Rui]

Rui

IC 11 / L780S09



PIN 1= 18.16V

PIN 2 = 0V

PIN 3 = 0V

PIN 4 = 8.47V

PIN 5 = 0



IC 9 / 78M05



PIN 1 = 0V

PIN 2 = 0V

PIN 3 = 0V



IC 10 / S-81250HG



PIN 1 = 0V (G)

PIN 2 = 9.77V (IN)

PIN 3 = 0V (OUT)



Checked CAP 2200UF/16 OUT 18.16V



THANKS RUI
-----

 

[mooose2]

After fitting the new internal battery, have you ;ressed the reset button behind the front facia panel?

 

[Rui]

Aor 3000A

After fitting the new internal battery, have you ;ressed the reset button behind the front facia panel?

Hi mooose2 ,
I have done that [still nothing] I think it the IC-10 (S-81250HG), but I can not fine it pc-borad, here in south africa they do not have a replacement on the IC-10 (S-81250HG) and I am waiting for a member to help thank for replying

regards
Rui [member]

 

[csialv]

Hi again. Sorry for the delay but I was on vacation.

Are the measurements you write in previous message with the switch on or off?

If measures are taken with the switch in ON, IC-11 IC-10 does not exit. Try to bypass to ground the pin 4 of IC-11 (78S09) and Tell.

Have you tried to do with the internal reset switch behind the display board?

 

[Rui]

Aor 3000A

Dear Csial,

I hope you had a good holiday, “power” meaning plug in on to the scanner ( but on and off switch on the front panel is “off “

I have rechecked !!

Check 1 with power : Checked CAP 2200UF/16 OUT 18.16V
Check 2 with power : fuse of positive 18.16 v
Check 3 with power : IC 11.. L780S09

Leg 1: 18.16v
Leg 2: 0.0v
Leg 3: 0.0v
Leg 4: 8.42v
Leg 5: 0.0

IC 9 78M05

Leg 1: 0.0v
Leg 2: 0.0v
Leg 3: 0.0v

The problem I can not fine or not sure were is IC-10 (S-81250HG), I can not see it on top of the pc board or is it at the bottom… BUT there is a purple wire from from leg 1(pin L780S09) that go to a IC but I not sure if its IC 10… I have check for S-81250HG to buy but nothing here in south Africa can replace it with some else ?

Can you tell me were to find IC 10 on the board

If you can send me your email I can send you a picture, is this your email csialv@yahoo.es

Thanks very much!!!!
Rui

 

[csialv]

While there is no exit in pin 5 of IC-11 there is no exit or entry into IC-9. Try forcing the output of IC-11 bypassing "Strobe" (pin number 4) to ground.

The IC S-81250HG (voltage regulator) is SMD type (SOT-89 mini power mold) and is in the back of the PCB.

I guess you can replace it with a 78L05 to 5V supply and is also small, just to have patience. The pins of 81250HG, left to right are GND, Vin, Vout. Visit the link:

Datasheet Archive - Semiconductor Datasheets, Electronic Component Datasheets

Keep me informed, please

 

[Rui]

AR-3000a

csialv.
Thanks for the info how ever I do not understand want you mean by say "Try forcing the output of IC-11 bypassing "Strobe" (pin number 4) to ground"

Thanks
Rui

 

[csialv]

IC-11 has only output voltage when input voltage at its pin 1 and when the strobe pin (pin 4) is set to ground (0 volts). The strobe signal at the receiver AR-3000A is controlled through the transistor Q31, which receives signal from the microprocessor board through pin 2 of connector J9. If you apply 0 volts to pin 4 of IC-11, forces the output of 9 volts on pin 5. Anyway still failing 5V voltage in IC-10 you say.... To test, measured at pin 1 of connector J9 and see if there are 5 volts. All measurements with the switch to ON.

 

[csialv]

IC-11 has only output voltage when input voltage at its pin 1 and when the strobe pin (pin 4) is set to ground (0 volts). The strobe signal at the receiver AR-3000A is controlled through the transistor Q31, which receives signal from the microprocessor board through pin 2 of connector J9. If you apply 0 volts to pin 4 of IC-11, forces the output of 9 volts on pin 5. Anyway still failing 5V voltage in IC-10 you say.... To test, measured at pin 1 of connector J9 and see if there are 5 volts. All measurements with the switch to ON.

 

[Rui]

AR-3000a

Csialv,
There are no words to say.. but a big thanks you for your time and help, I just hope that member can see you are a true member to this forum, there should be 6 ****** stars for the help you been give me as a member

I will do what you have ask me to do and let you know what is the outcome

Regards
Rui

 

[Rui]

AR-3000a problems solved

csialv,
you have solved the problem after checking and replacing:

battery CR2032 and replaced
also changes 2200uF/16V electrolytic capacitor replaced
checking (78M05, and replaced, checking L780S09 no power output on pin 4)

The fault was IC-10 (S-81250HG that provides +5 V to power the digital section), replaced it with 78L05 or 78M05 the pins were not same = pin 1 input, pin2 ground. pin 3 ouput.

but i changed the pins to fit the S-81250HG and it worked

the ar 3000a is working, but i found that NFM is very " fuzy" if i tune in to a FM Radio.. maybe its the antenna, however my normal FM radio works fine and ideas ?

thanks again

 

[csialv]

Congratulations Rui. I'm glad that you've managed to final repair your receiver. Never sell, insustuible for some tasks.

I have a question, did you find replacement for 780S09?

For noise in FM reception can not help feel that's much more complicated for my poor knowledge.

Congratulations again.

 

[Rui]

AR-3000a 780S09

Csialv,
Sorry no luck with 780S09 and not even find the replacement on the "MOD", not here in south africa, however I going to london next week and I hope member can tell me where in london I can get 780S09 and if I do get it, I will send you by post if need be.

So Member out there where can I buy a 780S09 in london,hopefully in the down town

Csialv thanks again for your help

Regards
Rui