ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi All
Have just bought a nonworking BL7000 for my BS6500, backlight not working, and 2-way not working.
Also, the "lift" function does not work..
So.. Changed caps and backupbattery(0.20v), and now 2-way is working again, and the remote remembers it's settings.
But while testing the lift function, I found some funny behaviour. When laying the remote on the table, it wakes, but without backlight, and the top red display turns off, as it always does when moving. After the 5 seconds or so, it normally takes for the move, then the red light comes on again. Still no backlight though.
Then I lift the remote from the table, the red display turns off, and the backlight comes on ???? then after the 5 sec move, the backlight again turns off ??
And just to clarify.. there is NO physical movent happening when this is going on..
What the he... is going on here ? :)
Anyone have any great ideas ?
/Weebyx
Bonus info..
Just looked at the motordrive, and everything seems fine. With the rubberbelt off, I can see that the motor actually is trying to lift the remote, but the motor runs very slow, and has no torque at all, when it is lowering the remote, the motor spis very fast and with some torque behind it..
I suspected the battery, but it measures almost 7v, and seems to hold charge very good.
Since the rest of the remote is working(timer programming, settings, 2.way, panel setup and so on) I think this must be a transistor or something that is not doing its job, or whatever else is responsible for the motordrive...
Ideas are welcome
Lidt hjælp
Thanks MCB
I have been doing a lot of measuring...
What I have found is that on the VCC side of the 10ohm resistor, there is 4,6v in both up/down movement,but on the TR27 side there is 0,5v when moving up, and 4,6v when moving down..
This results in a voltage over the motor when moving down, of 1,6v and 0,3v when moving up, the up voltage should be around the 4,3v.
I have simulated the circuit, and all the voltages match up between the BL7000 and the simulator.
Has anyone with a bit more electronic knowledge than me, any idea if this can be caused by a malfunctioning power resistor TR26/27/28/29 ?
And the second part is, how does this affect the backlight issue also ?
Just had an idea.. what if P5-7 and P5-8 is shorted somehow ? P5-8 is actually controlling the backlight..I had an issue with backlight on another BL7000, but that was caused by a faulty transistor which caused the transformer to not working. This however was affecting no backlight at all.. And since this problem is causing the backlight to work when moving down..
Ok , his is a great example of that sometimes it helps writing stuff to other people :)
it seems that my theory on the shorted/bad contact in pin 7-8 in P5 might have been the issue. I decided to get the cable out, and although it is glued to the pcb, I managed to do it.
both the cable and connecter showed signs of some surface coroding.. So I cleaned both with alcohol and a cue tip as good as I could, assembled it, and behold..... Everything works again :)
/weebyx