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Forum Index : Microcontroller and PC projects : PROJECT GEMINI IS ALMOST READY TO  LAUNCH

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Rickard5

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Joined: 31/03/2022
Location: United States
Posts: 463
Posted: 09:28am 29 Aug 2022
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Just waiting on a few more parts from Amazon and Mouser




I may be Vulgar, but , while I'm poor, I'm Industrious, Honest,  and trustworthy! I Know my Place
 
Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
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Posted: 11:16am 29 Aug 2022
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It's coming along nicely. :) Nice extruded case. I like that stuff.
Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs
 
Kabron

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Joined: 30/11/2017
Location: Germany
Posts: 65
Posted: 01:03pm 29 Aug 2022
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Why so?
 
Rickard5

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Posted: 04:16am 30 Aug 2022
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  Mixtel90 said  It's coming along nicely. :) Nice extruded case. I like that stuff.


Thanks Mick, and Thank you for all your Support and walking me though the Regulator thing on a Remedial level :) 20 years ago I did so AutoCadd Drafting for an Oilfield equipment company that used those Extrusions of all sizes from the size of a pack of cigarettes to the size of Dual 8" Floppies. Anyhow I showed up one Friday with a Case of beer for the Shop Guys Lunch time BBQ, and hit up the shop Forman for Drops (chunks too small to use) and he loaded up a 40 - 50 pound box of assorted sizes, and I been using them up for years, and I'm starting to run out :( but I'm looking forward to Project Apollo, and hope there will be one! We choose to build FAST Basic Computers in this decade and do the other things not because they are easy, but because they are hard. Because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we're willing to accept.
I may be Vulgar, but , while I'm poor, I'm Industrious, Honest,  and trustworthy! I Know my Place
 
Rickard5

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Posted: 04:16am 30 Aug 2022
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accidentale duplicate post
Edited 2022-08-30 14:22 by Rickard5
I may be Vulgar, but , while I'm poor, I'm Industrious, Honest,  and trustworthy! I Know my Place
 
Mixtel90

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Posted: 06:27am 30 Aug 2022
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  Kabron said  Why so?

Why do I like it?
I've used it on a couple of projects, including a valve+MOSFET headphone amp, where it looks really classy! It's nice to use where you need a bit of screening and mechanical strength. It also makes an excellent heatsink, a property that I used on a class D amplifier.
Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs
 
Rickard5

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Posted: 02:46pm 30 Aug 2022
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  Mixtel90 said  
Why do I like it?
I've used it on a couple of projects, including a valve+MOSFET headphone amp, where it looks really classy! It's nice to use where you need a bit of screening and mechanical strength. It also makes an excellent heatsink, a property that I used on a class D amplifier.


Mick Please don't take me down the Amplifier rabbit hole :) Right now I have 2 block amps wanting Tubes I can't find or AFFORD, I've been looking for the Right headphone amp forever now! But to your Great approval I've been considering mounting the LM1117T to the case, due to being wired to board, and now I HAVE No Choice. Now that you have mentioned the Heat Sink if I mount it on the board it will smoke the PCB, so I'm going to mount it to the case. Speaking of which, I been looking for a Lucas 3 position power switch (Off - smoke - On). I can only find the 2 position (off - Fire) ones in stock

The reason why there was no British space program was that the when first two astronautswere climbing into the first british space capsule one looked down at the dashboard and saw a little plate that read "Electrics by Lucas." Brave men, but not suicidal,they both refused to fly... 

I shouldn't joke about Lucas the Prince of Insufficient Light on this a most Historic Day, On this Day in 1921,  Joseph Lucas invented the Short Circuit.

I have a vague recollection of a Gemini 3 post-flight news conference during which the astronauts were asked how they solved a computer glitch in orbit. John Young raised his leg and said he just kicked it. so if my Gemini 1 Knows what's best for it, it better work first try every try

and as a Texan Memories of owning a A BSA 441 and a MG Midget Lucas left me wishing for old Soviet Electrics
Edited 2022-08-31 00:59 by Rickard5
I may be Vulgar, but , while I'm poor, I'm Industrious, Honest,  and trustworthy! I Know my Place
 
Mixtel90

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Posted: 03:44pm 30 Aug 2022
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My headphone amp is based on the "Starving Student" design. Circuit





I can *highly recommend* this design. Everything runs in pure class A, so the MOSFET heatsinks are spaced off so that air can circulate. They run quite warm. :) Power is provided by a 48V HP printer power supply.

-------------

The LM1117T won't get hot with a 5V supply. At most it's dissipating about 1/3W.
Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs
 
Rickard5

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Posted: 12:28am 31 Aug 2022
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Mick
That is cool I'm going to look in to that Amp, here are my Babies (4 ohm Magnepan plainers) I'm currently driving them with a Pioneer elite Receiver and they are Power hungry beasts

I have a PMVGA design#2 I've been meaning to build thanks to Al18 Thanks Brother I got all the parts now so I'm gonna get on it. Going though some of the extrusions I have left I found one the Perfect size (about 120 mm x 120 mm and 400 mm long And my current plan is to build in a CMOY Amplifier , This op amp amplifies voltage which high impedance headphones need. So the Major upgrade will be that I can plug in a set of unpowered speakers, Also by using the the Bigger case I'll have room for plenty of expansion boards!
I may be Vulgar, but , while I'm poor, I'm Industrious, Honest,  and trustworthy! I Know my Place
 
palcal

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Joined: 12/10/2011
Location: Australia
Posts: 2006
Posted: 12:52am 31 Aug 2022
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Sorry this is getting off topic, I built this amp. 55 years ago. It had a rebuild a couple of years back to update the caps but still has the original 6GW8 valves.



Edited 2022-08-31 10:53 by palcal
"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"
 
Rickard5

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Posted: 02:04am 31 Aug 2022
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Thanks Palcal now I have Tube Envy :) now if I could get enough Audiophiles interested in building a Picomite Based Moog type Synth and a Picomite Based Drum Machine Ohh boy wouldn't that be cool

Imagine building a MOOG like euro rack Synth from Picomites, Like having one Standard Module, that becomes anything by changing the software and I/O so the same module can be the Function Generator and with a software change and maybe add some pots it becomes the LFO Ect.....
I may be Vulgar, but , while I'm poor, I'm Industrious, Honest,  and trustworthy! I Know my Place
 
Mixtel90

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Posted: 06:42am 31 Aug 2022
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MMM....  planars... with stereo cats too! Lovely, Rick. :)

Proper Ali and Iron, Palcal. :) At least those valves are still available (although not particularly cheap). So, triode amp, concertina phase splitter then the pentodes in pp at a guess?

I have a couple of Russian directly heated triodes - a bit like small 2A3s but with 6V filaments. They would be nice single-ended, but the iron is *very* expensive now as is the electricity required to run them! The room would be warm though.

-----------------

The token on-topic bit:
Rick:
The top ground planes on that pcb is connected to GND, the bottom one is floating. Any sort of fixing that can connect to the top ground plane will connect the case to GND, so watch out for anything that could get shorted, particularly if the board is loose in the slots. Anything already connected to GND is fine, of course, but not stuff connected to 5V or 3V3. :)  Just one of those little perils as it was designed to fit a moulded plastic case.
Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs
 
Mixtel90

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Joined: 05/10/2019
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Posts: 8304
Posted: 06:46am 31 Aug 2022
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It's surprising how far you could get with a Pico Moog. PLAY SOUND can do sine, square & triangle but you've no noise generation.
Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs
 
palcal

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Joined: 12/10/2011
Location: Australia
Posts: 2006
Posted: 08:04am 31 Aug 2022
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@Mixtel90,   I bought a spare set of valves just in case. I am a member of the Historical Radio Society of Australia and they have a valve bank of over 5000 valves.
So I got them at a very reasonable price, I think they were about A$15 each.
"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"
 
Rickard5

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Posts: 463
Posted: 08:26pm 31 Aug 2022
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  Mixtel90 said  MMM....  planars... with stereo cats too! Lovely, Rick. :)...........................

I have a couple of Russian directly heated triodes - a bit like small 2A3s but with 6V filaments. They would be nice single-ended,....................The room would be warm though.

-----------------

The token on-topic bit:
Rick:
The top ground planes on that pcb is connected to GND, the bottom one is floating. Any sort of fixing that can connect to the top ground plane will connect the case to GND, so watch out for anything that could get shorted, particularly if the board is loose in the slots. Anything already connected to GND is fine, of course, but not stuff connected to 5V or 3V3. :)  Just one of those little perils as it was designed to fit a moulded plastic case.


Mick I live inTexas Bring the Warm Hollow State Valves we got AC freeze ya cold enough to cut glass :)

Mick once those Magnepan MP4 Plainer loudspeakers were Backed up by my Naim but unfortunately I had to sell my Naim to the highest bidder and become a Naimless NOBODY because you're a Nobody with out a Naim! Currently they are driven by a Pioneer elite Receiver, Cassette, 200 disk DVD Jukebox and all the DAQ you'll ever need I can spend hours talking about Hi-Fi stuff

I got those speakers and a Naim in trade for work, the Girl I lived with at the time was not amused so we had a spirited discussion about it and she threaten to go home to her parents. so 30 min latter I was helping her load up and holding the door so it wouldn't hit her in the Bum on the way out, I consoled m self by listening to Roger Waters - What God Wants ,God wants a clean fight, God wants a new HiFi

The Token On- Topic Response
Mick
Thank you for the Advice on the GND plane, I'm super paranoid about shorts and thankfully the PCB on Gemini is about a mm narrow of the case so I cut a reclaimed PCB to fit the Groove as a carrier board and I'm going to use low rise 3d printed plastic stand offs and Kapton tape as insulator :)
Edited 2022-09-01 06:29 by Rickard5
I may be Vulgar, but , while I'm poor, I'm Industrious, Honest,  and trustworthy! I Know my Place
 
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