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DirtBag Deluxe and the X-Vive MN3005

Started by Cybercow, June 07, 2020, 04:18:05 PM

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Aentons

Ok, so I'm deliberating on whether or not to order a TR, since they are currently in stock, and maybe trying to adapt it to my needs.

Ignoring the voltage requirements for a moment....Would ithe TR still work in a multieffect enclosure with the power wires between effects daisy-chained? The other effects in the enclosure would have the regular negative ground. Would it need to be isolated in some way?

Aentons

Would it be foolish to think of chaining two road rage boards?

Use the -9v tap off the first as the input for the second to get -18v and send that to the TR? Would that even work?

madbean

No, I do not recommend that. Build it as designed or find something else that suits your specific needs. You're probably just going to encounter a lot of trouble trying to rig some alternative power scheme.

Aentons

Quote from: madbean on July 23, 2020, 03:54:09 AM
No, I do not recommend that. Build it as designed or find something else that suits your specific needs. You're probably just going to encounter a lot of trouble trying to rig some alternative power scheme.
Ok, thanks... just thinking out loud here. Are you recommending against using an
inverting charge pump in general for the TR? If i I were to use just a single pump with +18v in and use the -18v output for the TR. Would that be a viable solution?

danfrank

LT1054 charge pumps have a max voltage input of 15 volts.
Have you looked at the Man o War Deluxe? The only thing the MOW doesn't do is feedback oscillation. The MOW modulation is more versital than the TR's modulation.
AND you could use a Road Rage and 12 volt regulator to power the MOW with 9 volts in (common pedal power)

Aentons

#20
Quote from: danfrank on July 23, 2020, 06:11:46 AM
LT1054 charge pumps have a max voltage input of 15 volts.
I did not realize that, thanks. I now see from the datasheet that it has a 1.1v drop as well so, even if I put +15v into the input, it would only give me around 13.9v which I assume is prob unacceptable for powering the bbd. Forgive my ignorance as I am fairly new to chargepumps, is there not another charge pump/inverter out there that would be acceptable for use with the TR if it is built as designed/recommended. I think the recommended EHX power adapter is 100mA. I don't see the power draw in the TR doc, but stinkfoot has the bigbox DMM draw at 41mA. Is that the maximum it needs or should there be a certain percentage of overhead to account for if I were to look for a suitable replacement for the LT1054?

Quote
Have you looked at the Man o War Deluxe? The only thing the MOW doesn't do is feedback oscillation. The MOW modulation is more versital than the TR's modulation.
AND you could use a Road Rage and 12 volt regulator to power the MOW with 9 volts in (common pedal power)

I have looked at it and have very seriously considered just going that route, but... For the foreseeable future, I'm probably only gonna build one analog delay and have com to the realization that if Im going to spend the time doing it, might as well be the one I really want.

BTW, I'm trying to accomidate this beast. I've been working on it for a while. I definitely plan more than I build. It's slow going.


I'm basically using a onespot type power (9v 1700mA) to it, it's actually using the P3 system from the amp over a TRS cable to the 1/4" jack on the pedal(the same jack is input for power, output for audio). So there is no dedicated power connection to the box. Just the TRS that carries audio and power, and then they are split using a stereo jack. Which is the IO/power module you see on the far right. I don't currently have any filtering after that so I should prob add a roadrage or other power board to it, and that why I keep harping on the TR requirements

I have about 30 boards in various stages of completion and they will all be modules for this. The TR is obviously the odd one out power wise so just trying to see if there are any accomodations that can be made for it to run as a module.

Scruffie

You would need a charge pump circuit capable of both inverting the 9V voltage to -9V, doubling it (with losses) to a minimum -17V and providing at least 50mA current supply.

You also need it to be high enough frequency and clean enough to not interact with the DMM's on board clock or any other clock based circuits you have running on the same power supply.

So to sum up, what you're asking for doesn't exist.
Works at Lectric-FX

Aentons

Quote from: Scruffie on July 23, 2020, 07:02:46 PM
You would need a charge pump circuit capable of both inverting the 9V voltage to -9V, doubling it (with losses) to a minimum -17V and providing at least 50mA current supply.

You also need it to be high enough frequency and clean enough to not interact with the DMM's on board clock or any other clock based circuits you have running on the same power supply.

So to sum up, what you're asking for doesn't exist.

Ok, just to make sure I'm out of luck on the TR....

What if I were able to just send +18v to get -18v? Are you saying an inverter that can handle 18v and output 50mA doesn't exist either?

madbean

The MAX634 might be able to. I've never used it but it does appear to meet some of the needed criteria.

Scruffie

#24
Well if you had 18V from a supply (not another charge pump) then you could use a 15V regulator, lift its ground pin by one diode drop to 15.6V to avoid the 16V terminal voltage and make up for the internal losses, in to a LT1054 and invert and ditch the on board regulator from the total recall.
Works at Lectric-FX

Aentons

Quote from: Scruffie on July 23, 2020, 09:18:52 PM
Well if you had 18V from a supply (not another charge pump) then you could use a 15V regulator, lift its ground pin by one diode drop to 15.6V to avoid the 16V terminal voltage and make up for the internal losses, in to a LT1054 and invert and ditch the on board regulator from the total recall.
Hmm, very interesting idea... With it's absolutely max being 16v for the LT1054 and the recommended operating range topping out at 15v, would sending 15.6v into it be running it hot and chance it burning up

Aentons

Quote from: madbean on July 23, 2020, 08:55:01 PM
The MAX634 might be able to. I've never used it but it does appear to meet some of the needed criteria.
Thanks for the suggestion. That one looks like the absolute max is 18v and the top recommended is 16.5v. How close can you typically get these things to the max before they are no worky?

madbean

Quote from: Aentons on July 23, 2020, 11:21:30 PM
Quote from: madbean on July 23, 2020, 08:55:01 PM
The MAX634 might be able to. I've never used it but it does appear to meet some of the needed criteria.
Thanks for the suggestion. That one looks like the absolute max is 18v and the top recommended is 16.5v. How close can you typically get these things to the max before they are no worky?

The Max634 has adjustable output so you you should be able to supply it +9v and get -15 out with 50mA  or more available. At least, that's what I'm getting from the datasheet. It looks like it's internal oscillator can be set to 40kHz so same ballpark as the LT1054.

Scruffie

#28
I suspect using it is going to be above Aentons pay grade (I wouldn't be keen on having to use it!), it's less a charge pump and more a SMPS, it'll need specific parts choice and very good layout.

For a chip from 1986 there's not much information on its use.
Works at Lectric-FX

Aentons

Quote from: Scruffie on July 24, 2020, 09:23:55 AM
I suspect using it is going to be above Aentons pay grade (I wouldn't be keen on having to use it!), it's less a charge pump and more a SMPS, it'll need specific parts choice and very good layout.

For a chip from 1986 there's not much information on its use.
Unfortunately, you might be right... Plus, the IC is roughly $5 and it requires an inductor that costs about the same or more, so that might be a relatively expensive solution.

Thanks guys!, I'll definitely start looking into some of these ideas.


...sure would be nice if there were a negative ground version of the TR that was maybe on the drawing board... (: hint,hint,wink,wink,nudge,nudge,sorry :)