Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - Jazz P Bass

Pages: [1] 2 3 ... 14
" switchmode amplifier, PWM (pulse width modulated) amplifier and Class-D amplifier"

Amplifier Discussion / Re: peavey musician series 400
« on: August 08, 2020, 01:09:50 AM »
!!!"  DISCONNECT any speaker"!!!

The Newcomer's Forum / Re: FX loop noise
« on: August 06, 2020, 11:43:38 AM »
Try the guitar into the Zoom & then go into the FX Return jack.
This will tell if it is a Send circuit issue or a Return circuit issue.
Be aware that you may have to adjust the gain on some of the Zoom presets.

Amplifier Discussion / Re: Crate G130C Amp
« on: July 24, 2020, 12:51:35 AM »
To answer the posts question, here is a crop of the power amp board locating D16 (+16Vdc) and D17 (-16Vdc)

Amplifier Discussion / Re: Crate G130C Amp
« on: July 23, 2020, 11:51:25 AM »
Piease post the relevant schematic.
You really should test the power supply before assuming the failure mode is the exact same.

-7Vdc on the speaker out connection indicates a failed output section.
The lower minus part is turned on when it should not be.
Do not hook up the speaker until this is resolved.

You will have to remove the old solder from the PCB before you install the new jack.
You will need a solder sucker,
Or 'solder braid'.

Amplifier Discussion / Re: Peavy 130 Special needs some TLC
« on: July 10, 2020, 12:09:48 PM »
Here is the schematic.

Schematics and Layouts / Re: Scholz UDG Schematic
« on: July 01, 2020, 01:26:08 AM »
Pretty rare pedal.
They only made about 100 or so.

Schematics and Layouts / Re: Kustom amp schematic
« on: July 01, 2020, 01:24:13 AM »
Call Kustom & ask for a schematic.

Pin 1 & 8 of the LM386 set the gain.
You are supposed to use an e cap (10uf) for more gain.
Not a jumper wire.
No cap and the gain is set to 20.

You will have to install something to limit the gain.
Some of the Zoom patches are off the wall high gain.
I have often wondered why they chose to do this.
You go from one one patch to the next one in line and the gain is off the charts.

Amplifier Discussion / Re: Rocktron Rampage R80
« on: June 25, 2020, 01:19:50 AM »
Or, if the FX loop is not being used, you can simply leave a patch cord installed.

Amplifier Discussion / Re: Rocktron Rampage R80
« on: June 22, 2020, 02:39:19 PM »
I would run a patch cord from the FX Send jack to the FX Return jack.
The Return jack has Normally Closed contacts that if they get dirty will prevent the signal from passing through to the power amp.
As to a schematic. Have you tried contacting Rocktron?

Pages: [1] 2 3 ... 14