Iron Pumpkin(s) and other smaller vegetable animals, Tips 'n' Tricks thread

in your case, change is simple : make front plate for TFT, mount Logic module (plus IR sensor and rotary encoder) on it, mount it on case, connect wide and narrow flat cable to Motherboard, solder 3 thin wires between MoBo and module; that's it, power On, enjoy


package consisted of :

-assembled Logic module with 3.5" TFT screen, programmed and tested
-IR sensor with cable
-encoder with cable
-fancy Al slab remote control (Apple TV buttons arrangement)
-flat cables for Turtle and for input select
- CAD, pdf and Sketchup files necessary to produce front plate for TFT window (e-mailed)

250E, shipping and Paypal fee included in price

possible even for for first one ..........Vitalica have Iron Pumpkin (bal) first gen, with two channel pcbs

as Logic package was developed later, I also resorted to big Motherboard approach, making physical controls (as you have now - two rotary switches) and logic module absolutely compatible electrically, so matter of choice which controls one will end with

controls in first gen had common Neg Rail (meaning that +Rail for relays is switched) and for Logic module is necessary that +Rail is common, while relay negs are switched

thus we (Vitalica & Moi) needed to make specific changes for all relays in his Turtle ( rotating all diodes parallel to relay coils) and same for all input relays

then some cutting and small wires work on channel pcbs, adding small relay PSU aside, and connecting entire Shebang..... pretty extensive e-mail correspondence to get all that done

anyway, even that is possible, but tedious work if you're not breathing and living solder, especially if you already have Iron Pumpkin singing and now you must butcher it in pieces again :rofl:

Funny TFT Logic module

example how it's done for Iron Pumpkin No.001


though, in this moment ....... while working on assembly of few IP kits already ordered, I'm in a middle of solving logistic problems, getting in quantity - Metglas (and finally! Finemet) cores, same as fancy Al slab remotes ....... as taught from Big Guy, I hate dealing and thinking in small quantities (even if production is limited by my own capabilities, number of heads and hands)

Life is fun ..... :rofl:

Holà Mr. ZM! 🙂

Do you have one in stock for my version of single large PCB?

also, wish list for future version if you decide to make a new revision one day. Do you think it could be possible to add gain per source? I know it would mean connecting extra flat ribbons and adding extra logic and software programming, but it would be a great feature.

All the best!
Do
 
yeah, I have all parts for Logic module, few remotes (but also awaiting new shipment of remotes, finally found viable solution to get them from our Chinese pals without too much hassle)

regarding gain change per input ...... naah

more complexity inside of preamp, more complexity in code - all solvable in elegant way, but if I think of possible complication with someone not so savvy with user programming procedure, and all that just to make change of gain in bracket of 8db .......

not going to happen

I didn't include balance ...... who needs that ?
 
Now I have a problem.

I first connected Turtle Iron Pumpkin with zero gain to F6 an I enjoyed it for weeks. Fantastic combo.
Then I tried a M2x letting Pumpkin, still with zero gain, drive the autoformer direct. The combo revealed details I never heard but lacking low bass.
So I hooked Pumpkin, with some gain, to F4 and found my absolute comfort bliss.

My problem now is that my DIY curiosity hit the brake. 🙂

/Lossless-Gungnir-Pumkin-(dual external PSU and amp)-Cornwall III and some diy cables.
 
My Pumpkin has reached the stage that the lid can be put on the case 🙂
Here are some pictures of the final version with the arduino remote developed by Berny.
Great sound and ease of use 🙂
 

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When I installed the remote in the pumpkin I noticed that I had some hum on volumes greater than step 10.
So off to hum hunting, it finally turned out that the small 10VA EI transformer I used for the arduino was the guilty one,
replaced with a toroid and the noise levels dropped 25db !

Here some measurements (vol 15) of three different PS versions:
The first version had R-cores and a small EI for the arduino,
second version still R-cores and a EI, but preregs added before the shunt
third version all transfo's replaced with toroids from Toroidy and Talema, Bingo 🙂
 

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Hi Danny, it looks really good, I like your build!
I'm now collecting ideas for the build as my vegetable is on way, maybe Santa will be able to drop the parcel down in front of my door next week 🙂
Do you have a link for your remote control with the display?
 
that cute display - it was starting (well, one of) phase of my logic module development

I got software and basic setup from guys but then - I was too stupid, too stubborn and had higher ambitions

couldn't manage with their code, so started learning and with some help, ended with all new code....... also for fancier screen

anyway, considering everything, it wasn't walk on the Beach ...... it took me considerable burst of energy to learn from 0, what I successfully avoided for a decade or so :rofl:

cute small display: Iron Pumpkin Logic development 05 of 10 - YouTube
 
Hi Plott,
One word of advice: do not use EI cores 🙂

The remote control was developed by Berny, he's also here on diyaudio.
The software/architecture of the remote control was shared with ZM,
on which he based his own development,
documented in 10 episodes on youtube 🙂
 
agree for EI cores...... though - Iron Pumpkin 001 ( practically that one endured entire development process) was having in one of instances - two EI Core xformers , each 30VA or so, without any side effects

though - those xformers are of insane pro quality, properly made to cruise all day long on full power, without sweating; go figure

Code - luckily I got help from one of local guys (highly skilled software Engineer), and he said - "I know how to make that for you, but I don't have time; I'll help saying what to do, and will help when you're in trouble"***

what was working to my benefit was:

- he didn't laugh much on your Code and my semisemisemiliterate attempts to make it work;
-he then pushed me to start from clean slate, both regarding learning things and then writing code ( starting with same display because Libraries are small and actually working)
- he was laughing cheerfully later when I opted to second display ...... second was a Breeze, proper library and all necessary datasheets and web wide examples clearly shown

- he was laughing cheerfully and slightly mocking, urging me to sleep sometimes, when I started with third and final display ...... nothing worked - supposed Libraries are not working, supposed connection protocol wasn't working ....... and regarding web wide examples with same display - what can I say - as Dr. Haus said - "Everybody lies"


in short - tried multiple Libraries to make it worlk, ending with oophteenth one, and even that one I needed to edit;

with that , display is working when directly connected on top of Mega2560; problem was smaller Mega2560 Pro - different pinout and misleading^X! display datasheets, saying nothing about protocol;

then - my brilliant idea of having custom fonts,not existing for Arduino; then I needed to learn how to convert them for Arduino (easy) and how to convert them to work in used Library ( ooking not easy)

Luckily, somewhere in the process I forgot why I started it and who was/is main NudgeNudger for entire adventure ....... so didn't blame Pa when I was most desperate ........ and didn't sent him an email with @#%$!!%!%%%%!!!!!&!!&!&! :devilr: !!!!!



***resulting in fact that Cannon-meat 95% of Code is mine, while most important 5% of Code is his............ besides entire merit for me writing 95% is his too ..... :rofl:
 
Hello ZenMod,
I finished my second Iron Pumpkin and now i have a problem. It runs in our living room with a cd player with 2,3V RMS, a diy Aleph J and a Klipsch La Scala.
And at -48dB it sometimes is too loud. So i think i need another 6 dB of attentuation.
Your buffer has a R out of max. 25 Ohms and the Aleph J has an R in of 240Kohm.
Witch values should i take for the resistors in a voltage divider between IP out and Aleph j in? I think 2x 4K7 will do the job. Or should i go lower?
Ralf
 
though, it is time to think how to organize system better in terms of gain - wasting so much of signal is simply ...... waste, even if volume setting being in xformer domain

amp with lower voltage gain

F4, or M2 without autoformer in - would suffice for your needs
 
you are absolutly right, and i have already ordered parts for F4 , but that will take a while.
And i love the sound of Aleph j with my Klipsch. I also built a M2 and it sounds very good with pop and jazz but with classic the Aleph j is much better.
It warms up the sound of the Klipsch. The Klipsch stands there for about 33 years and the Aleph j is the best amp i heard so far.
And it is only the living room system........
Ralf