Help fixing up Rowe Ami CD100

[Liamo81]

Hello all, first post after browsing here for months. I've been hunting for a Rowe Ami CD jukebox to tidy up for my house and finally got my hands on an old Laserstar CD100 the other day. It's a bit tatty and needs some work, but we'll pleased with it as bought it as spares and have got it back to life already.

I've no previous experience with them so have been reading up on them on the forums for months whilst I searched for one, now I hoped I might pick some knowledgable brains for a bit of advice with it?

The title rack pages flip fine inwards, but when trying to flip them back the other way as soon as you press the button the machine appears to reboot after a twitch of the pages. The screen will read Checksum, ram test etc and then back to normal. On the third attempt, the pages will flip once, and then repeat the above. This is the same whether the button on the front is pressed, or on the service switch. Any idea where best to start with this?

The other issue with it is volume randomly getting louder or quiter without being adjusted. No errors/warnings come up. Saw the suggestion on another thread perhaps recap the amp?

Does anyone know a UK supplier of Rowe Ami parts? I'm on the South coast.

Thanks all in advance!

Liam

[lilshawn]

the motor and power supply is probably getting weak. the increased load of trying to turn the page causes the voltage to dip and the computer to reboot.

if you are feeling up to the task, rebuilding the power supply with new capacitors will help with that initial surge torque of the motor flipping the page. it may help keeping the computer from rebooting.

failing that, the motor could be too far gone. I'm not sure which motor you have there flipping your pages, but i know they went through a few iterations of motors. some better than others.

the power supply also went through a couple of revision changes... they are all fundamentally the same, just updated with newer parts. The 61086501 board is a much better designed board with modern components and much better active power regulation.

[Liamo81]

Hi,

Thanks for the tips.

It seems odd the motor works fine in one direction but not the other. I can't see a Rowe part number, but it's marked Merkle Korff industries 26-67-27-GM. Is it still possible to get replacements?

The power supply is marked 60937701. I've ordered capacitors so will try and give that a go.

Any ideas on the sound going up and down? Any components in the amp/pre-amp that are likely to need changing?

Thanks.

Liam

[Liamo81]

Oddly enough having just wiggled the connectors on the motor when getting that part number it's now working both ways so another problem sorted!

Two to go, dodgy sound and mute circuit not working?

Liam

[lilshawn]

The amp has a dips witch that ended and disables "AVC"  or automatic volume control.  Try disabling it if it's enabled... Or enable it if it's disabled.   
 
The mute circuit is a single wire connector to  the computer.  It is orange with a black stripe.  Make sure it's plugged in.

[Liamo81]

Thanks Shawn, at work today so will have a look tomorrow and report back.

Liam

[Liamo81]

Can't see any dip switch for AVC on the amp, only Mono/Stereo. The amp part number is 61024901.

I've had a play about with it, oddly the graphic controls don't seem to do anything at all, and the sound issue seems to cut one channel whilst raising the volume up and down on the other. Seems the pre-amp is sick I guess.

Any suggestions?

Thanks.

Liam

[lilshawn]

double check your volume connection on the bottom of the amp (white and purple wires.)

double check your volume connection terminal strip. you should have the jumper installed as mono if you have a single volume pot (2 wires) and as stereo if you have dual volume controls (or single stereo) with 3 or 4 wires

the stereo/mono dip is on the left, AVC is on the right. it may not be labeled  depending on how old the carcass is.

[Liamo81]

Hi again.

Sorry for the delay, I was away for a few days.

Checked volume control, jumper and dips, still with no joy.

I've pulled the amp apart now and found that one of the driver boards has scorched or hot  looking components at R7, R10, R13, CR13, R25, R26, R31, C8, R28 and C12.

Looking at the Darlington transistors, the corresponding pair appear incorrect as they are 2N6285 and 2N6282. The other pair are correct spec but not matched. No fuses or breakers were blown.

Does this shed much light on my sound problems? Any ideas what difference the out of spec transistors will have made?

Cheers chaps.

[Liamo81]

Both the pre-amp and driver boards have clearly all had repairs at some point so not immediately clear which burnt bits of board have already been sorted before.

Cheers all.

Liam

[Liamo81]

Just found a cracked/cold joint on one of the legs of Q3 on the other driver board as well, so looks like a few things to be getting on with.

[lilshawn]

it's quite common for those components to get cooked if the transistor output gets shorted to the input gate. throws high voltage into the board. no good.

i believe the resistor values are 470 ohms and 180 ohm

there is also a PNP transistor "MPSA56" that blows too.

I'm not sure if the exact location of the components, i just have a "repair" box with my amp components of the most common parts that go all together in the box... but those are the values.

[Liamo81]

Thanks Shawn, will report back soon.

[ami-man]

Hello all, first post after browsing here for months. I've been hunting for a Rowe Ami CD jukebox to tidy up for my house and finally got my hands on an old Laserstar CD100 the other day. It's a bit tatty and needs some work, but we'll pleased with it as bought it as spares and have got it back to life already.

I've no previous experience with them so have been reading up on them on the forums for months whilst I searched for one, now I hoped I might pick some knowledgable brains for a bit of advice with it?

The title rack pages flip fine inwards, but when trying to flip them back the other way as soon as you press the button the machine appears to reboot after a twitch of the pages. The screen will read Checksum, ram test etc and then back to normal. On the third attempt, the pages will flip once, and then repeat the above. This is the same whether the button on the front is pressed, or on the service switch. Any idea where best to start with this?

The other issue with it is volume randomly getting louder or quiter without being adjusted. No errors/warnings come up. Saw the suggestion on another thread perhaps recap the amp?

Does anyone know a UK supplier of Rowe Ami parts? I'm on the South coast.

Thanks all in advance!

Liam

Hi Liam,

We are in Sheffield if you need parts or help sorting out the amplifier etc.

Regards
Alan

Alan Hood
ami-man
UK
alan-hood@datex.co.uk

[Liamo81]

Evening.

So I bought a new set of output transistors, and all the resistors, diodes, caps and transistors I needed to overhaul my driver boards. I replaced the TIP31C transistor at Q3 on the left driver board and that seems to have fixed it. Been playing all day without the previous sound problem occurring. Thanks for the advice.

Got a pile of parts I don't need now though!

Liam

[lilshawn]

it can't hurt to have spares. these amps are a little uppity when you start adding speakers and tend to blow the main transistors if the improper connections are made. (these amps need a very specific speaker load on them)

but...you can always sell them here on the site in the buy/sell/trade subforum if you really think you won't need them.

glad you are up and going now. You'll find it sounds great. Rowe made a great sound system.

[Liamo81]

Loving having the jubebox playing properly. I've got another plea for assistance though...

The incandescent bulbs in the animation unit had been changed for an RGB LED strip which half the lights had blown it. I bought another strip and replaced it, but which only lastex a couple of days and burnt out.

I've now bought a set of individual 12v RGB slow flash LEDs to go into it. I've tested one wired to the 14v supply for the lights. It had worked fine on a 9v battery, but now hlowed only red, got very hot and began to smoke.

Can anyone advise what resistors or diodes I'd need to connect in line to run LEDs safely? Many thanks.  Liam

[lilshawn]

I think the voltage feeding that display is AC volts not DC. you'll need to check.

you can use it by installing a "bridge rectifier" (or make one)... (and maybe a smoothing cap) to convert it to DC volts.

this can be done with a ready made component or with 4 diodes. maybe a 220uF cap on the output to smooth out the flicker.

LED strips don't particularly like reverse voltage it gets on the flip side of the AC waveform. DC only.

double check your voltage. if an LED strip is rated for 12 volts. better to give it 12 like it says. going above will shorten it's life.

[ed12]

the 14 is ac not dc


ed

[Liamo81]

Cheers guys. Had a feeling it was AC but thought I had it wrong seeing as it had a working-ish LED strip in when I got it.

[Liamo81]

Fixed it today.

Made a bridge rectifier out of 4 1N4007 diodes. Connected two sets of 4 LEDs wired in series with a 150ohm resistor to each set of 4. All working, bit dimmer than I hoped for but no more burning out.

Thanks for the info.

Liam

[ed12]

now add a filer cap to the + / - sides of the bridge
wala the lights get pure dc
470mf @ 25vdc will do fine
or if u are using a center tap?
 have 1 to the + side of the bridge and 1 to the - side of the bridge
!!mind your polarity!!
use the center tap as return for the 2 of them


ed

[lilshawn]

yeah you're gonna lose a bit through the diodes. but you got what you got. i'm glad you figured it out.

you'd lose a little less with a proper ready made rectifier...voltage drop is generally a little less. but hey... a handful of 4007's is like 7 cents.

a cap is a good idea too. will get rid of the weird flicker you see in it.

[Liamo81]

Thanks for the tips. Will probably swap it out for something a bit tidier and more permanent in the future but I guess it looks alright and is working fine for now.

Next job is to make 100 title cards!