Dumble clone (Ceritone) OTS50

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Re: Dumble clone (Ceritone) OTS50

Post by dbharris »

JMPGuitars wrote: ↑
Fri 11/10/23 5:21 pm
dbharris wrote: ↑
Fri 11/10/23 4:49 pm
for instance my digital scope doesn't do a good job for this task
What scope are you using that can't handle that?
Hey Josh, I am sure it's user error...I have a Hantek DSO5102P. I can always use it pretty easily, but this particular task I could not figure out a way to have the signal at both cathodes displayed in a manner that showed the changes to each introduced by adjusting the PI trimmer. And as far as I can tell, I can only use the "measure" function for one channel at a time.
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Re: Dumble clone (Ceritone) OTS50

Post by JMPGuitars »

dbharris wrote: ↑
Fri 11/10/23 7:48 pm
Hey Josh, I am sure it's user error...I have a Hantek DSO5102P. I can always use it pretty easily, but this particular task I could not figure out a way to have the signal at both cathodes displayed in a manner that showed the changes to each introduced by adjusting the PI trimmer. And as far as I can tell, I can only use the "measure" function for one channel at a time.
Oh, sorry. No offense, but almost everybody I've heard of that has a Hantek scope says...don't buy a Hantek scope. I've never had a Hantek, but that's how I feel about Rigol. I'm guessing it's more useful than the haters claim. 🀷

You're probably right about the math function being limited to 1 channel, but why do you need a math function? What are using the math function to track?
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Re: Dumble clone (Ceritone) OTS50

Post by dbharris »

JMPGuitars wrote: ↑
Fri 11/10/23 10:56 pm
dbharris wrote: ↑
Fri 11/10/23 7:48 pm
Hey Josh, I am sure it's user error...I have a Hantek DSO5102P. I can always use it pretty easily, but this particular task I could not figure out a way to have the signal at both cathodes displayed in a manner that showed the changes to each introduced by adjusting the PI trimmer. And as far as I can tell, I can only use the "measure" function for one channel at a time.
Oh, sorry. No offense, but almost everybody I've heard of that has a Hantek scope says...don't buy a Hantek scope. I've never had a Hantek, but that's how I feel about Rigol. I'm guessing it's more useful than the haters claim. 🀷

You're probably right about the math function being limited to 1 channel, but why do you need a math function? What are using the math function to track?
It's not a very user friendly scope. Buy once cry once and all, but I did cheap out on this purchase and it shows. The goal is to get the amplitude of both signals to be exactly the same.

That's why using the DMM also works because the signals are obviously opposite at the those cathodes when you measure across them (and not with respect to ground). By setting to mv resolution, when the DMM reads 0 they are matched. Too far in either direction and it will swing positive or negative.
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Re: Dumble clone (Ceritone) OTS50

Post by JMPGuitars »

dbharris wrote: ↑
Sat 11/11/23 7:00 am
It's not a very user friendly scope. Buy once cry once and all, but I did cheap out on this purchase and it shows. The goal is to get the amplitude of both signals to be exactly the same.

That's why using the DMM also works because the signals are obviously opposite at the those cathodes when you measure across them (and not with respect to ground). By setting to mv resolution, when the DMM reads 0 they are matched. Too far in either direction and it will swing positive or negative.
Amplitude isn't a Math function, it's a function of Measure. The manual doesn't make it clear if you can measure from multiple channels or not, but I assume you should be able to. Page 33 covers measurements: http://www.hantek.com/Product/5000P/DSO5000P_Manual.pdf

It does say you can display 8 measurements at once, so it's possible you can select the channels for each, but you have to experiment with that.

On my scope, I select the channel, then select the measurement type. Here's a quick example I setup:
SDS2504XP.png
Thanks,
Josh
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Re: Dumble clone (Ceritone) OTS50

Post by dbharris »

JMPGuitars wrote: ↑
Sat 11/11/23 11:02 am
dbharris wrote: ↑
Sat 11/11/23 7:00 am
It's not a very user friendly scope. Buy once cry once and all, but I did cheap out on this purchase and it shows. The goal is to get the amplitude of both signals to be exactly the same.

That's why using the DMM also works because the signals are obviously opposite at the those cathodes when you measure across them (and not with respect to ground). By setting to mv resolution, when the DMM reads 0 they are matched. Too far in either direction and it will swing positive or negative.
Amplitude isn't a Math function, it's a function of Measure. The manual doesn't make it clear if you can measure from multiple channels or not, but I assume you should be able to. Page 33 covers measurements: http://www.hantek.com/Product/5000P/DSO5000P_Manual.pdf

It does say you can display 8 measurements at once, so it's possible you can select the channels for each, but you have to experiment with that.

On my scope, I select the channel, then select the measurement type. Here's a quick example I setup:
SDS2504XP.png

Thanks,
Josh
Thanks, I will give that a try next time I have a chassis out of the headcab!
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Re: Dumble clone (Ceritone) OTS50

Post by foreverstrung »

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Re: Dumble clone (Ceritone) OTS50

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Glad you got this up and running! What speaker are you playing through? It sounded good, this was just clean then OD, no PAB or Mid Boost?
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Re: Dumble clone (Ceritone) OTS50

Post by foreverstrung »

Glad you got this up and running! What speaker are you playing through? It sounded good, this was just clean then OD, no PAB or Mid Boost?
Yes. I didn't even really go to far into the OD or mid boost at all. My main objective with this short clip was just to show how silent it was. I never really get the true output or sound recording with an Iphone 14

The speaker is a WGS Blackhawk. It's actually the speaker for my TMB w/Reverb build. I've got a 16ohms Celestion Cream laying around I was going to use in the speaker cabinet I'm going to build for this. Not sure how it'll sound. Love this Blackhawk, but I've got the pricey Cream speaker just laying around. I don't really want to spend $300 on another speaker if I don't have too.
Thoughts?
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Re: Dumble clone (Ceritone) OTS50

Post by foreverstrung »

Not so fast!
I'm having some problems with the OD. It appears the preamp is the only dirt i'm getting. The OD trim pot and main pot are doing nothing. Presence is having little to no influence on the OD channel either.Trouble shooting now.
Likely pulling out the scope
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Re: Dumble clone (Ceritone) OTS50

Post by foreverstrung »

So for some reason, (human error), I've dropped the OD signal all together. Went thru the voltage chart again and all my voltages look good. Put a scope on it and am getting no signal at the OD channel. Replaced V2 tube, still no change. I'm posting a pic of the schematic and then a point on the diagram that IDK what it means. Any help is appreciated.
IMG_0607.jpg
What does this mean?


IMG_0606.jpg
The rest of it, tho there are some modifications/additions
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Re: Dumble clone (Ceritone) OTS50

Post by JMPGuitars »

It's drawn as two switches and a pot. The two switches could actually be one DPDT switch, but I'm not familiar with the amp. I assume it is a DPDT switch.
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Re: Dumble clone (Ceritone) OTS50

Post by dbharris »

That's the channel switching relay. But it is drawn a little weird on the schematic and it looks like they omitted the PAB relay on the schematic. As long as you followed the layout and used the correct relays, it should be fine. It looks like there is an under board jumper on the Channel relay board. Does your PAB relay work correctly? You can also use the manual/pedal switches on the back to test that way.

Probably good to pull out the scope and start signal tracing.

In terms of the speakers, I bet the cream will sound good. G12-65 and EVM 12L are the favorites.
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Re: Dumble clone (Ceritone) OTS50

Post by foreverstrung »

That's the channel switching relay. But it is drawn a little weird on the schematic and it looks like they omitted the PAB relay on the schematic. As long as you followed the layout and used the correct relays, it should be fine. It looks like there is an under board jumper on the Channel relay board. Does your PAB relay work correctly? You can also use the manual/pedal switches on the back to test that way.
Nik at Ceritone told me that the layout has some things that are not in the schematic and to stick to the layout.
I did catch that underboard jumper yes. It's clear on the layout.
My schematic reading skills have improved since last year, but I'm still real new.
The PAB does work very well. I've got the OD working now too, but not like it did originally or as it should. OD is only working when the footswitch toggle is engaged. (set for pedal), without the pedal even being connected. With the pedal connected, they both work as they should. PAB and OD
This amp has been like whack a mole tho with little issues. Now the rock/jazz toggle does nothing nor does the tone stack. I get sine waves through the treble, mid and bass, but the treble, (which is directly connected to the rock/jazz toggle), shows no increase increasing/decreasing the sine signal. Mid and Bass do show sine increase/decrease adjusting the pot, but when the guitar is plugged in, all 3 knobs of the tone stack don't do squat that I can hear and as I said, the rock/jazz switch does nothing..........When I started fiddling with the completed amp, they all worked. Now that I've been dicking with it, IDK what i've done.
Yet!
It's the journey, right?
With the volume on 2, OD and PAD about halfway and my guitar on 6/7, this amp shakes the house. Sounds awesome. Full of relatively clean grit. But I know it'll even be better once I get this tone stack figured out.
Attached layout
Overtone-Special layout pdf.pdf
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Re: Dumble clone (Ceritone) OTS50

Post by dbharris »

foreverstrung wrote: ↑
Wed 11/15/23 5:16 pm
That's the channel switching relay. But it is drawn a little weird on the schematic and it looks like they omitted the PAB relay on the schematic. As long as you followed the layout and used the correct relays, it should be fine. It looks like there is an under board jumper on the Channel relay board. Does your PAB relay work correctly? You can also use the manual/pedal switches on the back to test that way.
Nik at Ceritone told me that the layout has some things that are not in the schematic and to stick to the layout.
I did catch that underboard jumper yes. It's clear on the layout.
My schematic reading skills have improved since last year, but I'm still real new.
The PAB does work very well. I've got the OD working now too, but not like it did originally or as it should. OD is only working when the footswitch toggle is engaged. (set for pedal), without the pedal even being connected. With the pedal connected, they both work as they should. PAB and OD
This amp has been like whack a mole tho with little issues. Now the rock/jazz toggle does nothing nor does the tone stack. I get sine waves through the treble, mid and bass, but the treble, (which is directly connected to the rock/jazz toggle), shows no increase increasing/decreasing the sine signal. Mid and Bass do show sine increase/decrease adjusting the pot, but when the guitar is plugged in, all 3 knobs of the tone stack don't do squat that I can hear and as I said, the rock/jazz switch does nothing..........When I started fiddling with the completed amp, they all worked. Now that I've been dicking with it, IDK what i've done.
Yet!
It's the journey, right?
With the volume on 2, OD and PAD about halfway and my guitar on 6/7, this amp shakes the house. Sounds awesome. Full of relatively clean grit. But I know it'll even be better once I get this tone stack figured out.
Attached layout
Overtone-Special layout pdf.pdf
When you are tracing the signal through the tone stack, make sure PAB is off. Is your rock jazz switch a 3 position? If so, PAB is also activated in the middle position.

You may want to chopstick solder joints and the shielded cables. Some shielded wire is more finicky than others and it can be easy to overheat when soldering causing an intermittent connection between the shield and conductor.

One you get all the bugs ironed out, I would highly recommend you build a dumbleator buffered effects loop. Even if you don't want to run effects in the loop, it will allow you to crank the amp for the sweet spot in tone while keeping the output volume wherever you want. It works way better than an attenuator since these amps are really about preamp distortion.
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Re: Dumble clone (Ceritone) OTS50

Post by foreverstrung »

When you are tracing the signal through the tone stack, make sure PAB is off. Is your rock jazz switch a 3 position? If so, PAB is also activated in the middle position.

You may want to chopstick solder joints and the shielded cables. Some shielded wire is more finicky than others and it can be easy to overheat when soldering causing an intermittent connection between the shield and conductor.



One you get all the bugs ironed out, I would highly recommend you build a dumbleator buffered effects loop. Even if you don't want to run effects in the loop, it will allow you to crank the amp for the sweet spot in tone while keeping the output volume wherever you want. It works way better than an attenuator since these amps are really about preamp distortion.
This was totally just user error. Tone stack is fine. The PAB being activated was/is the issue. It's only a 2 position switch, but when the PAB is activated, there is no tone stack.
I ordered a "Dumbleator". Chassis and parts anyways. I'll put it together. Install it with my new head.....
I'm really enjoying getting to know this amp. Lots of variations.
I'll post pics of the Dumbleator and then the cabinet fabrication after on this thread.
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