Carlsbro glx 150 head

[ska-head]

Hi, i bought myself a second hand carlsbro glx 150 half stack, and to start with it was really great. But then i started getting a huge amount of electrical interference on channel 2 ( drive ). then channel one started going really quiet, before one day the amp head made a loud pop, and now the head wont even turn on. Any advice or suggestions would be very much appreciated. Thanks

[Chuck H]

Well a loud "POP" is inducative of something acutely failing. But you do mention that the amp was losing something prior to the acute failure. Still, I think finding the most recent failure is where we need to start. So...

Did you notice any smoke or a funny smell, light show? Is there any sound at all, even hum or buzz?

[ska-head]

it is important to understand I know very little about amps. The cab makes not noise at all, but they is a very very faint hum from the head. No lights turn on when i turn it on. And im not entirely sure how to get the back of the head off

[RODNEY]

I've got the schematic of the power stage for your head, the hum you hear is the transformer, there's two fuses just after the trans' these have probably blown so power is not getting to the amp circuit-board, but it's not that simple as replacing them, something has caused them to blown. Mine went the same, three of the eight power transistor had failed, not sure if this was the cause or as a result of something else going wrong. This is an on-going project of mine and I'm having to test every single F### component to try and fine the root cause. Anyway, mine was made in 1994 so i assume this schematic is fine for you. Just to mention, diode D3 doesn't seem to be on the schematic (fitted across the relay coil). Email me on rodneyjones68@hotmail.com and I'll send them to you.

[RODNEY]

Question for an electronics expert.
There's 4 high power (4 Watts) resistors on the circuit-board, 0.33ohm x 4, 0.1ohm x 1 and a 4.7ohm x 1, should these be non-inducting type or doesn't it matter?

[RODNEY]

F### me!! I've fixed it. I replaced all the power transistors and the four power resistors on the TIP35C x 2 and TIP36C x 2 emitter legs. Had a final poke around the board and found diode D11 moved so i just re-soldered it, put it back together, plugged in, switched on and it worked . Not bad for someone until two years ago didn't have a clue about electronics (OK.. i know two years it a long time) but I did get side-tracked during those two years with 4000 series IC and op-amps etc)
I'm ecstatic to say the least, cause it's an awesome sounding amp.
Final note....I used TIP41C and TIP42C instead of TIP31C and TIP32C, they are equivalent apparently.

[Chuck H]

Too bad you didn't find that loose diode earlier. Could have saved some trouble. Glad it's fixed.

[bobot62]

carlsbro glx 150c

Question for an electronics expert.
There's 4 high power (4 Watts) resistors on the circuit-board, 0.33ohm x 4, 0.1ohm x 1 and a 4.7ohm x 1, should these be non-inducting type or doesn't it matter?

gud day sir, i am new here and i have read that you have a schematic diagram of carlsbro glx 150c, i also have a problem with mine, can i ask you a copy of the diagram sir, tnx

[Chuck H]

The OP in this case has only two posts to his credit and that's almost four years ago. I wouldn't expect a response. But, you don't get anything if you don't ask.

[g1]

In post #4 above, there is an email address for someone with the schematic. The address may not be good anymore, but try it anyway.

[bobot62]

gud day guys, still have a problem with my glx 150c, it sounds good now but after some time using it, the ac fuse [2 amp ] will blow and when replacing and turning it again and sounds good but the thing is that it is hot, the chasis is hot, i think its not its normal temperature, what is the problem? need some help here, tnx

[RODNEY]

Just come accross this thread again, yes I have the schematics, e-mail me - rodneyjones68@hotmail.com if you still need them.

edit...ahh..just realised, yours is the GLX150C, mines with out the "c".