Dumbleator build questions.

[Fictitiousfreedom]

Hello everyone! Im in the process of building one of these, specifically Martin’s version with the buffer. I have one thing I’m confused about before I start. What exactly does it mean when it says G1 “isolated”? I know its ground but im a little unsure of how to go about isolating it? I assume its something very simple but I'm doing this build on a turret board and I’m in the process of drawing a layout and just want to understand the circuit completely before i start drilling.

Thanks, Camden

[martin manning]

Poor choice of words… it just means distant from the reservoir ground, as seen in the .pdf layout here: https://ampgarage.com/forum/viewtopic.p ... 34#p170734

[Fictitiousfreedom]

Poor choice of words… it just means distant from the reservoir ground, as seen in the .pdf layout here: https://ampgarage.com/forum/viewtopic.p ... 34#p170734

I just found you answering someone else in another thread, sorry i didnt find it before asking, but either way thank you! I appreciate your work and am so grateful for all of you guys. I hate to be a pest but one more quick one while i got your attention. Very simple and probably naive question. Is there a way to use a fender style bayonet lamp with the standard 6.3v bulbs with the 12v tap? I overlooked this problem when ordering and only have the typical bulbs. Im sure i could just use a normal led but id rather use the fender lamp simply because it will be easier to change the jewel color and replace bulbs because i have a huge stock of them.

Thanks, Camden

[martin manning]

Is there a way to use a fender style bayonet lamp with the standard 6.3v bulbs with the 12v tap? I overlooked this problem when ordering and only have the typical bulbs. Im sure i could just use a normal led but id rather use the fender lamp simply because it will be easier to change the jewel color and replace bulbs because i have a huge stock of them.

The standard Fender pilot lamp is a #47, T3-1/2 envelope with BA9s bayonet base, 6.3V at 150 mA. You could just put a resistor in series, 6.3/0.15 = 42 ohms at 2W. You could also use the LED equivalent to a #47, and add a resistor in line (value TBD). That would likely mean lower current draw, less heat, and longer life than an incandescent. There are 12V incandescent bulbs with similar specs, but that would be different from the ones you have.

[Fictitiousfreedom]

Is there a way to use a fender style bayonet lamp with the standard 6.3v bulbs with the 12v tap? I overlooked this problem when ordering and only have the typical bulbs. Im sure i could just use a normal led but id rather use the fender lamp simply because it will be easier to change the jewel color and replace bulbs because i have a huge stock of them.

The standard Fender pilot lamp is a #47, T3-1/2 envelope with BA9s bayonet base, 6.3V at 150 mA. You could just put a resistor in series, 6.3/0.15 = 42 ohms at 2W. You could also use the LED equivalent to a #47, and add a resistor in line (value TBD). That would likely mean lower current draw, less heat, and longer life than an incandescent. There are 12V incandescent bulbs with similar specs, but that would be different from the ones you have.

Thank you man, thats extremely helpful. I must've fudged the math because i had come to the conclusion it would take a big high wattage resistor somehow. Me and math have some problems with each other. I accidentally bought some 12v bulbs at some point but cannot find them anywhere, I’m pretty organized too so I'm wondering if it was a dream i had while obsessing over this stuff lol ill dig around for a 2w low R and give it a shot. So just to be clear the resistor would go in series with just one side of the winding at the lamp terminal? Sorry I've scoured and for some reason can not find any info on anyone doing this. Im using exactly the transformer in your schematic. Thanks again man!!!

When im done with my layout ill post it here, unless there is a better place. Since its apparently the year of the D’lator maybe once its looked over it can help someone else doing one without the use of a pcb.

[martin manning]

So just to be clear the resistor would go in series with just one side of the winding at the lamp terminal?

Correct. Just like putting another 6.3V bulb in series.

[Fictitiousfreedom]

So just to be clear the resistor would go in series with just one side of the winding at the lamp terminal?

Correct. Just like putting another 6.3V bulb in series.

Wonderful, thank you for the time brother, i am acutely aware of how valuable time is so its very much appreciated.

[Fictitiousfreedom]

I finished my d’lator, it works pretty good but i do have a few questions if thats ok?

I messed up and ordered the wrong BOM, after spending so much time making sure it was perfect i went and ordered an older one i had made. So i built the original instead of your buffered version. I still plan to make the changes later and have a layout for both. The only issue i have is the lamp, i tried what you suggested but it brought the entire heater string down instead of just the bulb. I added a 47R 2 watt in series with one half of the string as you said. I don't know what i did wrong, its a pretty simple concept. Im running it without an indicator which is less than ideal. I cant find a 12.6v bulb anywhere.

Also just to be sure its operating properly, i seem to have to have the drive maxed out for it to sound good. Especially the drives bright switch, its horrible unless the drive is maxed. It also seems the send level also needs to be quite high. I need to install a bypass in my loop so i can compare but to achieve unity gain the d’lator settings need to be really really high, which then starts to raise the noise floor. Other than that its great and im really loving the tone i get with it!

[dbharris]

I finished my d’lator, it works pretty good but i do have a few questions if thats ok?

I messed up and ordered the wrong BOM, after spending so much time making sure it was perfect i went and ordered an older one i had made. So i built the original instead of your buffered version. I still plan to make the changes later and have a layout for both. The only issue i have is the lamp, i tried what you suggested but it brought the entire heater string down instead of just the bulb. I added a 47R 2 watt in series with one half of the string as you said. I don't know what i did wrong, its a pretty simple concept. Im running it without an indicator which is less than ideal. I cant find a 12.6v bulb anywhere.

Also just to be sure its operating properly, i seem to have to have the drive maxed out for it to sound good. Especially the drives bright switch, its horrible unless the drive is maxed. It also seems the send level also needs to be quite high. I need to install a bypass in my loop so i can compare but to achieve unity gain the d’lator settings need to be really really high, which then starts to raise the noise floor. Other than that its great and im really loving the tone i get with it!

You may be best served by starting a thread in the discussion section. Something is wrong with your build if you have to run the pots like that. Please post clear pictures and voltages. Both versions are buffered by the way. Martin's version is just aimed at being more transparent than coloring the tone as HAD's does.

-Dan

[Fictitiousfreedom]

I finished my d’lator, it works pretty good but i do have a few questions if thats ok?

I messed up and ordered the wrong BOM, after spending so much time making sure it was perfect i went and ordered an older one i had made. So i built the original instead of your buffered version. I still plan to make the changes later and have a layout for both. The only issue i have is the lamp, i tried what you suggested but it brought the entire heater string down instead of just the bulb. I added a 47R 2 watt in series with one half of the string as you said. I don't know what i did wrong, its a pretty simple concept. Im running it without an indicator which is less than ideal. I cant find a 12.6v bulb anywhere.

Also just to be sure its operating properly, i seem to have to have the drive maxed out for it to sound good. Especially the drives bright switch, its horrible unless the drive is maxed. It also seems the send level also needs to be quite high. I need to install a bypass in my loop so i can compare but to achieve unity gain the d’lator settings need to be really really high, which then starts to raise the noise floor. Other than that its great and im really loving the tone i get with it!

You may be best served by starting a thread in the discussion section. Something is wrong with your build if you have to run the pots like that. Please post clear pictures and voltages. Both versions are buffered by the way. Martin's version is just aimed at being more transparent than coloring the tone as HAD's does.

-Dan

Ok thank you! Sorry, will do.

[martin manning]

The only issue i have is the lamp, i tried what you suggested but it brought the entire heater string down instead of just the bulb. I added a 47R 2 watt in series with one half of the string as you said. I don't know what i did wrong, its a pretty simple concept. Im running it without an indicator which is less than ideal. I cant find a 12.6v bulb anywhere.

You need to take he heater voltage directly from the PT and put the resistor in series with just the pilot lamp.

[pompeiisneaks]

I've moved this to a new thread in the dumble discussion section.

[Fictitiousfreedom]

The only issue i have is the lamp, i tried what you suggested but it brought the entire heater string down instead of just the bulb. I added a 47R 2 watt in series with one half of the string as you said. I don't know what i did wrong, its a pretty simple concept. Im running it without an indicator which is less than ideal. I cant find a 12.6v bulb anywhere.

You need to take he heater voltage directly from the PT and put the resistor in series with just the pilot lamp.

Of course! I feel quite silly about that one. It works now. I had to use a 50R 10w wire wound because thats all i had close to 47R. It is a bit overkill lol
My D’Lator sounds great with the original values, i still plan to try your newer circuit and i also need on-on-on switches so i can add some options. I think its running properly but i seem to need to have the gain pot close to maxed to sound good. If i put the recovery pots at 12 o clock i can get only get unity gain with the gain set to 3 o clock or higher. Is is the correct response?

My voltages are as follows…

Pin 1 - 330V
Pin 2 - 16V and 31V after the 1M resistor
Pin 3 - 36.3V
Pin 6 - 162V
Pin 7 - 0.9V

[martin manning]

Wha are the power supply voltages? They should be roughly 360 and 260.

[Fictitiousfreedom]

Wha are the power supply voltages? They should be roughly 360 and 260.

My power supply voltages are 325V and 240V, so a little low. Hmmm. I checked all of my values and they are correct for sure. Ill have to do some more reading and experimenting. It may be a transformer. Ill run tests later today if you have any helpful advice id be very grateful. Thanks!