Tevion LCD3209ID remote /IR receiver

[notallbad]

I don't have the original remote for this tv and don't seem to be able to get any universal remotes or Sky Rev.8 remote to control the tv.
I know its possible that these remotes don't have the correct RC5 command sets but would have thought one of them would at least switch it on.

DMM probe on IRIN pin on the SSB and voltage steady at 3.62v whilst in standby, with a universal remote in auto tune mode the IRIN volts fluctuates, sometimes drops as low as 2.76v but most of the time its just 3.4 to 3.5v, the voltage fluctuates in time with the remote led flashing in auto tune mode. I think this is pretty conclusive that the ir sensor is receiving remote commands.

The keys on the control panel work, vol up/down, channel up/down, menu, source. But to tune digital channels it automatically prompts me to 'accept' or 'cancel' but none of the panel keys do anything.

Is there anything suspicious here?

SSB voltage readings:
in stby tv on
5vsb 5.03v 4.93v
bklon 0v 4.9v -----looks good
pwm 3.2v 3.2v
op1 5.02v 4.92v
gnd 0v 0v

5v-s 5.03v 4.97v
gnd 0v 0v
irin 3.62v 3.6v
key 4.98v 4.92v
gled 0v 1.96v ----looks good
rled 1.77v 0v -----looks good

gnd 0v 0v
key1 4.98v 4.92v
key0 4.98v 4.92v

txd 3.21v 3.8v
rxd 3.21v 3.8v
gnd 0v 0v
5vstb 5.03v 4.96v

+12vin 0v 12.3v ----looks good
+12vin 0v 12.3v -----looks good
gnd 0v 0v
gnd 0v 0v
gnd 0v 0v
+5vin 0v 5.01v ----looks good
+5vin 0v 5.01v -----looks good
5v_s 5.03v 5v
pwon 0.16v 4.53v
+5vin 0v 5.01v -----looks good
+5vin 0v 5.01v -----looks good
gnd 0v 0v
gnd 0v 0v

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

Removed the IR board and found that the IR receiver has 3 pins:

Output
Gnd
Vcc

So there is 5v on the supply pin but only 3.6v on the output, which should be equal to the input until it receives a remote IR signal when it pulls down the output.

As the output is already 'pulled down' or so it would seem as it only reads 3.6v without any remote IR signal I thought I would remove and check. Sure enough with a 6v supply on the input there is also 6v on the output until it receives a signal.

So looks like I need to find what is pulling down the output on the SSB.

Now another thought is the parameter in Service Menu 'No Control', deactivates the remote sensor. How does it do that exactly? And of course without using a remote I am unable to gain access to the Service Menu, don't have Compair H/W, S/W etc...

[budm]

Re: Tevion LCD3209ID remote /IR receiver

Can you read any P/N on the IR?
Example:
https://cdn.badcaps-static.com/pdfs/...10499b7353.pdf
Link to the service manual?

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

B175? Thats all I can see on it!

An oscilloscope would be great at this point I guess!

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

I think Service Manuals for these makes are non-existant!

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

Does this look like it might be useful for direct control?

http://www.ebay.co.uk/itm/USB-to-UAR...item2317cc6f7a

[budm]

Re: Tevion LCD3209ID remote /IR receiver

Scope will be good to have right now.

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

Perhaps I shall just change the sensor to see what the results are in comparison.

I have a scope but not sure its working correctly or just not been calibrated perhaps!

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

Any views on this?

Tenma 72-6800

Asking £75 or near offer but may offer around £50, untested so may take a chance if the view is that its a relatively good scope.

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

So scope out for what its worth, lets see!

Pictures hopefully in order:
1. Probes shorted
2. Probes connected to IR board Gnd and 5v-s
3a and b showing probes connected to IR board Gnd and IRIN - the 2 pictures capture the solid line representing 3.6v roughly and the second photo with the voltage drop
I don't think this scope can capture the oscillation fast enough!#? Not sure

Scope set to 1v/cm, each grid is 1.5cm and 1ms time/cm, perhaps this should be slowed down to 1us time/cm.

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

Oh yes, 3b is showing the IRIN line with a universal remote in auto search mode, hence the drop in voltage.

[notallbad]

Re: Tevion LCD3209ID remote /IR receiver

Managed to control the TV with serial IR in the end so went ahead and purchased a remote, yipee all working.

Now for Service Menu code????
Unsuccessful so far, any ideas please!