Post your Solid State pics here.

[fotios]

With each humility i present 3 pictures of my dream for enough years which is my new project after an exhaustive work of 5 months.
Who is the Charisma? It is a stereo (dual mono arrangement with individual supplies for each channel) preamplifier whole of discrete devices consisted from two units. The first includes the power supply, the microcontroler unit and the big LCD display. It is a fully remotely controllable system. The second unit comprises the main analog stereo preamplifier; this includes 7 inputs: one phono, two balanced for CDs or DACs, two single for CDs or DACs and finally two single line level inputs. It is obvious from the photos the different input filtering arrangement for each type of source, and this is exactly the charisma of this project; when one source it is connected all the other sources are absolutelly inactive. With other words, this preamplifier works as a seven seperate sources, once per time. The outputs are: one direct record after the main buffer or the individual phono preamplifier but before the volume control, as well one balanced and two single outputs. The outputs are absolutelly seperated between them via the output mute relays.
Another one remark it is the absolute absence of any cable connection. I hate cables, thus i have spend a lot of time during the designing of PCB layouts.
The photos presents only the main board of the analog preamplifier unit. In the 2nd photo taken from the front, it is obvious the empty holes which addressed for the chassis mounted RCA or Phono sockets as they are all of the high quality type.The heart of the unit which are the seperatelly assembled discrete operational amplifiers they are ready but under examination at this moment on the workbench for taking measurements. After 2 days i will post photos of the completted analog unit. After one week also i will post the photos of the controll-power supply unit.
A meaningfull remark: all the PCBs are double sided and LITERALLY home maden from my hands. It is obvious the trick of the soldered wire jumpers to bridge the tracks from the component side to the solder side. This is reported to encourage you, to make (with few and inexpensive means) your own PCBs at home. For the record: The cost of these PCBs maden in a laboratory it is about 150 Euros. The total size of the PCB (which comprised from 2 seperate and bridged with gold pins between them PCBs of 190mm X 270mm each) it is 380 X 270mm. Instead the cost of these home maden PCBs it is about 25 Euros. For any information and help, i am available as usually.

Fotios

[fab]

Fotios,

Very nice job and really quitre impressive to do your own pcb at home with such apparent quality. In fact, I am curious to know what is the glazing green material you used and how it was applied to your pcbs at home.. How did you manage to make the mask to avoid green material to be applied to the soldering points?

Also, is the volume pot installed in the right direction for knob installation on the front plate ?

Thanks

Fab

[fotios]

Originally posted by fab
Fotios,

Very nice job and really quitre impressive to do your own pcb at home with such apparent quality. In fact, I am curious to know what is the glazing green material you used and how it was applied to your pcbs at home.. How did you manage to make the mask to avoid green material to be applied to the soldering points?

Also, is the volume pot installed in the right direction for knob installation on the front plate ?

Thanks

Fab

Hi Fab

Thanks for your kind words. For your questions now:
1) The glazing green material it is in reality a usual protective laquer for PCBs, but some special and difficult to obtain it. I understand very well your place, because also me i was in the same (with the transparent silicon or acrylic based protective sprays) and was a dream to me to obtain a such coating. The laquer it is the: Insulating and Encapsulating Spray SL 1360 S of PETERS GmbH. : http://www.peters.de. It is offered in a usually spray can of 400ml, it is based on polyurethane, it is solderable after drying (it melts about 300 deg C) but if you apply in the solder points a thin layer of tin on the copper before the encapsulating with the spray, this makes the job of soldering later easiest because the green paint mixed into the laquer it slides away from the tinned points as it appears in the photos. The spray, in contrast with the usual available in the electronic shops, it needs at least 24 hours to dry thoroughly and it is better to not accelerate this with hot air because the color will be scattered. The cost of spray it is about 20Euros which means that it is expensive in comparisson with the usual sprays of 10Euros for a can of 400ml, but the result it is beatyfull thus the double cost it is worthy. The difficult thing it is to obtain it, because the factory it is in Germany. Also we in Europe we can't find this spray easy (not Farnell not RS sell this product). I don't know if the DigiKey offers the spray. For my big luck, my local supplier of ONSemi in north Greece became the agent of PETERS in Greece before one year, thus i can obtain it very easy.
2) The motorized pot of ALPS, it is purposely placed in the inverse direction. The first reason it is to keep a distance of the usually noisy motor as far as possible from the sensitive amplification parts of signal. The second it is that i am not intented to place a manual operated knob on the front plate. The mot. pot. it is fully remotelly controllable by the MCU included in the second unit with the power supplies and also in the MCU (a PIC18F4520) incorporated the RC5 remote control protocoll of Philips. Thus with any inexpensive remote control with only 6 buttons can obtained the main functions: Mute, Stand By, Input Select+, Input Select-, Volume+ and Volume-. A set of six corresponding buttons it is also incorporated on the front plate of the control/PSU unit under the big LCD display. In few days, i will post the photos of this unit because it is under programming proccess at this moment.

Fotios

[Nelson Pass]

Very nice.

To quote Cassandra Peterson, "Stay away from the front of my car"

[dudaindc]

WOW!

[fotios]

Originally posted by Nelson Pass
Very nice.

To quote Cassandra Peterson, "Stay away from the front of my car"

From whose the car?

Thanks for your kind words.

Fotios

[roender]

Originally posted by AKSA
Mihai,

Beautifully made, the work of an artisan. When you add up the expertise in the design as well, much credit goes to you.

Cheers,

Hugh

Originally posted by Bonsai
I second AKSA here - superb job Mihai

Thank you very much!

[Mooly]

Absolutely first class, it really does put to shame many a commercial product. How did you get on with your printer by the way ? Methinks you need an A3 one
Regards Karl

[fotios]

Originally posted by Mooly
Absolutely first class, it really does put to shame many a commercial product. How did you get on with your printer by the way ? Methinks you need an A3 one
Regards Karl

Hi Karl

Thanks for your kind words. You are a good man, and this not due to your good words hear, but from our discusions in the other thread (making good pcb at home) and your interest to give me a help in my titanic effort for completing this difficult project. As for my printer, to the present it works sufficiently by 90%, not serious problems. As for your thought about an A3 size printer, i haven't moneys to spend for getting one. I am this moment in a very difficult place about my project and you will see in the following new post an explanation of this.

I will back!
Fotios

[EUVL]

> The laquer it is the: Insulating and Encapsulating Spray SL 1360 S of PETERS GmbH. : http://www.peters.de.

I cannot find the SL1360S at the Peters website as you mentioned. The only spray can products I can find in both their German and English catalog in pdf are SL1307 and SL1309.

Perhaps you could post a direct link to the catalog, and tell us where to look (which page) ?

Thanks,
Patrick