Hartke Main Board Schematic

[steelguy]

Hartke main board #4005198011 schematic needed. This board seems to be quite different than most other.
It has markings that read "3500B/5000/7000B". I called Samson and left a message for support, but have not received any calls. I really hate to start tearing into this board without a correct schematic, but will if I have to. Any help here appreciated.

[DrGonz78]

Before even looking for a schematic... Will you enlighten us to the symptoms of the amp? Maybe someone here has worked on this amp before?

[steelguy]

No output. All dc voltages normal. No blown fuses. No indication of anything burned. Just silent. I have a pretty good repair facility with scope, meter, sig gen, etc. Just want to be able to do some signal tracing before surgery.

[km6xz]

Have you verified that there is Send signal present at the insert jack? Does the speaker relay pull in? Does the Return jack when fed with a +4 signal, produce any response from the power amplifier. Be sure to keep loads off the amp until it is working fully with no offset at the emitter resistors for the power transistors. Don't go by the speaker terminals because if there was offset, the relay would disconnect the speaker terminal from the power amp anyway.
How much signal tracing have you done on it. Where does the signal stop?

[Enzo]

Does signal get to th power amp connector?


Which amp do you have? The board may cover the 3500B, the 7000B, and the 5000, but that doesn't tell us which you have. The board will not be stuffed the same for all models.

[jbltwin1]

Here's the schem if it works.

Hartke 3500 schematic.pdf

Guess it works!

Don't know if it's the same though-different numbers but same model.

[steelguy]

Here's the schem if it works.

[ATTACH]21905[/ATTACH]

Guess it works!

Don't know if it's the same though-different numbers but same model.

Success! Found bad solder joint on Effects Send jack. This is a model 3500B amp.
Thanks to all for your help.

[Joep]

Hartke main board #4005198011 schematic needed. This board seems to be quite different than most other.
It has markings that read "3500B/5000/7000B". I called Samson and left a message for support, but have not received any calls. I really hate to start tearing into this board without a correct schematic, but will if I have to. Any help here appreciated.

I have a HA5000 with Bi-Amp function and the same main board marked 4005198011. I cannot find the correct schematics. It has a different compressor design.
I need the schematics to troubleshoot an issue that ocasionally occurs. Unfortunately sometimes during a gig. The issue is that the signal is distorted and almost muted. It may go away after a while and sometimes when i hit the strings with a flat hand and cause a huge signal transient at the input it also goes away. I suspect that the voltage controlled amplifier in the compressor section gets stuck at a low gain level. Unfortunately this issue is not easy to reproduce.

I already resoldered the main board two times. I am pretty sure that this is ok now.
The issue is on the main board because it is audible on both power amp outputs.

Can anyone help?

[Enzo]

Turn the compressor off. That ought to tell you if teh compresor is involved. My first suspect would be teh FX loop jacks, or power amp in jack. If the cutout contacts in those get dirty, the signal comes and goes.

[Joep]

Turn the compressor off. That ought to tell you if teh compresor is involved. My first suspect would be teh FX loop jacks, or power amp in jack. If the cutout contacts in those get dirty, the signal comes and goes.

Thanks for your quick reply. I have checked the FX loop jacks but could not find any bad connections there. After another inspection of the main board I found one of the transistors in the compressor section (w/o schematic I guess the RMS detection) had a suspicious looking solder connection. I resoldered it and now using the amp and waiting for the issue to occur again or not.

One more data point that I forgot to mention: the issue seems to happen more often when I start using the amp in low ambient temperature (e.g. start playing in open air in the evening hours or after moving the amp from a cold storage room to a warmer rehearsal room).

I still would like to find the schematics of this main board, because it really is different from the HA3500 schematics that can be found on several sites on the Internet.

[Enzo]

COntact Samson and ask for it. The 3500 and HA3500 are not the same thing. CLose, but not the same.

[jonbo335]

Hello, any news for this shematics ? I have a problem with compressor but the shematic is not the ha3500 and 3500 mosfet

[shortcircuit]

Is this the right schematic ??
HA-3500 2018VCA Old Compressor.pdf
If it is, a tip of the hat to g1 for posting it for me.

[jonbo335]

Yes Sir, the schematic match all boards, there are some errors in the preamp design, missing pot of tube and solid state preamp...