Difference between revisions of "The Analog Thing"

From TheAnalogThing
(Updated Schematics on Main Page to v1.2)
 
(38 intermediate revisions by 6 users not shown)
Line 1: Line 1:
'''The Analog Thing''' (abbreveated as ''THAT'') is a small analog computer built for educational and recreational purposes by [[anabrid GmbH]]. The computer will be available for sale at the net cost of its components, i.e. as cheap as possible and not-for-profit. We are targeting a retail price of around EUR150. The component list, circuit diagrams and circuit board layouts of this computer are released as Open Source, and information on how to build it from scratch and how to operate it will be released here on this wiki.
+
[[File:Cta bg.jpg|thumb|A closeup of a THAT in [[Minion]] mode with [[Oscilloscope]] probes attached.]]
 +
'''The Analog Thing''' (abbreviated as ''THAT'') is a high-quality, low-cost, open-source, and not-for-profit cutting-edge analog computer developed by [[anabrid]] under the brand Analog Paradigm for educational and recreational purposes. THAT will be available for sale at a net cost price of around €300. The component list, circuit diagrams and circuit board layouts of THAT are all Open Source. Information on how to build THAT from scratch and how to operate it can be found on this wiki.
  
 
== Version 1.0: Specifications and Photos ==
 
== Version 1.0: Specifications and Photos ==
 +
The prototype consists of two main parts: A top PCB with gold-plated through-hole sockets suitable for
 +
2 mm patch cables, and a base PCB, which contains the main electronic circuitry, the
 +
manual controls and ports for external connectivity. A [[Panel Meter]] mounted in the top PCB can be used to display coefficient values and, when the device is set to the repetitive operation mode, its operation time.
 +
 +
The size of the analog computer is 203mm x 240mm x 35 mm (with knobs).
 +
 
<gallery>
 
<gallery>
 
   File:Promo 1.jpg|A first glance
 
   File:Promo 1.jpg|A first glance
 
   File:Front Board v1.0.jpg|Front board v1.0
 
   File:Front Board v1.0.jpg|Front board v1.0
 
   File:Base Board v1.0 patched.jpg|Base board v1.0
 
   File:Base Board v1.0 patched.jpg|Base board v1.0
   File:Test Circuit closeup v1.0.jpg|Some test circuit closeup
+
   File:Test Circuit closeup v1.0.jpg|Close-up of a test circuit
 
</gallery>
 
</gallery>
  
== Assembly instructions ==
+
== Schematics ==
The following sections describe the assembly process of The Analog Thing with BASE board revision 1.0, 04.2021. This board has some minor quirks that must be taken care of as described in the following.
+
The schematics and bill of materials for the base board are [[Open Source]] and can be found here: [https://github.com/anabrid/the-analog-thing]
  
Basically the assembly process is straightforward based on the [[:File:Bill_Of_Materials|bill of materials]] and is straightforward. The BASE printed circuit board should by assembled according to the following steps:
+
<gallery>
 +
  File:anathing_v1.2_base_1.png|BASE part 1
 +
  File:anathing_v1.2_base_2.png|BASE part 2
 +
  File:anathing_v1.2_base_3.png|BASE part 3
 +
  File:anathing_v1.2_base_4.png|BASE part 4
 +
  File:anathing_v1.2_base_5.png|BASE part 5
 +
  File:anathing_v1.2_base_BOM.pdf|Bill of materials BASE  
 +
</gallery>
  
* First, solder in all resistors, capacitors, inductors, transistors, and diodes but leave out R24, R25, D1 and C26, C28, C30, C32, C35, C27, C29, C31, C33, C34 (we will come back to these later). (A nice introduction to soldering SMD parts by hand can be found at [[https://josepheoff.github.io/posts/howtosolder-11soldersmdpassive]] or at [[https://mansfield-devine.com/speculatrix/2018/05/adventures-in-smd-soldering-part-1-by-hand/]].) It is advisable to solder in each type of component at a time. All parts denoted with a * in the bill of materials are high precision parts, i.e. resistors with 0.1% of precision etc. '''Attention:''' The positive side of the 47&mu;F capacitors is denoted by the dark stripe on the capacitor! '''Attention:''' The markings for C5 are the wrong way around on the PCB! The dark stripe of C5 must point upwards to the connector end of the BASE board!
+
The schematic of the FRONT PCB can be found here:
* In the next step, solder in IC2 (LM4040x) and all connectors except the 1x4 pinhead for the connection of the panel voltmeter (we will come to this later, too). Please note that the rear connector of the Cinch connectors must be trimmed slightly with a side-cutter as the through hole in the PCB is a tad to small.
 
* The next step involves soldering in the DC/DC-converter IC1 (TBA2-0522).
 
* Solder in switch J12 (lower right).
 
* Solder in the trim resistor R14.
 
  
Having finished these tasks, the first test can be performed:
+
<gallery>
 
+
  File:anathing_v1.2_front_1.png|FRONT part 1
* Set the switch J12 to its second position from the fully counter clockwise position (this is OFF).
+
  File:anathing_v1.2_front_2.png|FRONT part 2
* Connect THE ANALOG THING to a suitable 5V source via the USB cable.
+
  File:anathing_v1.2_front_BOM.pdf|Bill of materials FRONT
* Now switch J12 to its fully counter clockwise position (this is MINION mode which implicitly turns on the circuit).
+
</gallery>
* check that all supply voltages are present and valid:
 
** Check for -12V at pin 11 of IC25.
 
** Check for +12V at pin 4 of IC25.
 
** Check for +5V at pin 14 of IC23.
 
** Check for +5V at the lower left pin of IC2.
 
 
 
If these tests turn out to be OK, the rest of the board can be populated with parts:
 
 
 
* Solder in all remaining ICs.
 
* Solder in 1nF WIMA PP capacitors as C26, C28, C30, C32, and C35. These are the integration capacitors for the large time scale factor of the integrators. The result should look as follows: [[File:1nF_WIMA.jpg|500px]]
 
* Solder in the five 100nF capacitors C27, C29, C31, C33, C34 in the lower part of the PCB: [[File:100nF.jpg|500px]]
 
* Now it is time to solder in switch J11, and the potentiometers R16-R23 and the potentiometer R100. '''Attention:''' R100 is a 100k potentiometer with a logarithmic (!) curve while the potentiometers R16-R23 have a linear resistance curve. These potentiometers look basically identical and can be distinguished by the markings at their back: [[File:lin_log_potentiometers.jpg|500px]] The potentiometers marked B1 are of the linear type (R16-R23) while the potentiometer marked A2 is the logarithmic potentiometer R100.
 
 
 
Now a minor fix must be made to allow for operation of the digital panel voltmeter (DVM). Originally the DVM should have been supplied by the +12V supply of THE ANALOG THING. Unfortunately this does not work since the inputs of the DVM are not referenced to ground (GND). To compensate for this the supply of the DVM must my changed to be symmetrical with respect to ground. By means of two Z-diodes two voltages of about +/-6V are generated which are then used to power the DVM:
 
  
* Solder in the 1x4 pinhead J13 but bend up its top pin so that it does not touch the through hole in the PCB.
+
== CAD and Gerber files ==
* Solder in a BZX84 6V2 Z-diode in the place of D1.
+
{{Todo|Upload the Gerber files here}}
* Short circuit the two pins of this Z-diode either with a short wire or with a 0 Ohm resistor.
 
* Solder a second BZX84 6V2 Z-Diode with its anode to the bottom connection of C60 (as shown below) and connect its cathode with a thin wire to the topmost pin of the 1x4 pinhead connector. The result should look like this: [[File:dvm_patch.jpg|500px]]
 
* Now it is time to solder the four connector cable to the DVM. In addition this bridge P3 on the back of the DVM must be opened and P1 must be closed to set the decimal point to its correct position: [[File:dvm_connections.jpg|500px]]
 
  
The remaining steps are:
+
[[File:THAT-Dimensions.png|thumb|A first glance at the dimensions of THAT]]
* Install the four plastic spacers on the BASE board and snap in the pre-drilled plexi-glass sheet.
 
* Install the four hexagonal spacers in the corners of the BASE board: [[File:base_pcb.jpg|500px]]
 
* Snap the DVM with its attached four connector cable into the FRONT PCB.
 
* Connect the DVM cable with the 1x4 pinheader J13.
 
* Mate FRONT and BASE PCBs (the two 50 pin connectors require some patience as well as some deliberate but careful force to fully close).
 
* Secure the FRONT PCB with four screws in its corners.
 
* Plug the knobs to the axes of the switches and potentiometers.
 
  
That's it! You should now have a fully working ANALOG THING. :-)
+
The size of the PCB is 201mm x 240mm. The overall height (including feet and front panel potentiometers) is 38mm. The height of the two PCBs (without screws) is 16mm. Note that the base PCB has throught hole components, thus feets are mandatory (at least 2mm in elevation). The weight is approximately 900g including cables.
  
== Testing ==
+
We have digital [[3D Models of The Analog Thing]] in the wiki.
The next step should be to test your ANALOG THING thoroughly.  
 
  
* Adjust the DVM and check the coefficient potentiometers:
+
== Instructions and further reading ==
** First of all, set the mode control switch on the bottom left to OFF.
 
** Connect THE ANALOG THING to a 5V USB power supply by means of a USB-A/USB-A cable.
 
** Set the mode control switch to COEFF. In this mode the coefficient potentiometers can be set with the DVM showing the current value of any of the eight coefficient potentiometers COEFF 1..COEFF 8.
 
** Set the COEFFICIENT switch to 1.
 
** Set the potentiometer COEFF 1 fully counter clockwise. The DVM should now display zero (a slight deviation from zero is permissible, so a displayed value of 0.003 would be OK, too).
 
** Now turn the potentiometer COEFF 1 fully clockwise.
 
** Adjust R14 (left side of THE ANALOG THING) with a tiny screw driver until the DVM displays 1.000.
 
** Check the remaining potentiometers by stepping the COEFFICIENT switch through positions 2 to 8 while setting each of the remaining potentiometers first fully counter clockwise and then fully clockwise. The DVM should display (nearly) zero and 1.000 in these two cases.
 
  
* Test the summers and inverters:
+
* [[Assembly instructions]]
** Set the mode switch to IC (initial condition).
+
* [[Testing]] instructions
** The following steps are to be performed for each of the foud summers:
+
* [[Components of The Analog Thing]]
*** Connect the jack labelled U on the front panel with one of the output jacks of the summer being tested. Connect one of the inputs with weight 1 with the machine unit -1 (lower left corner of the patch field). The DVM should display a value very near to +1.000.
+
* [[The Analog Thing FAQ]]
*** Connect the -1 machine unit shortly with one of the summer inputs weighted with 10. The DVM must show a value in excess of 1.100 and the overload indicator OL should be lit.
 
** Perform the first of these steps with each of the four inverters. (Do not connect -1 or +1 directly to the summing junction input SJ.)
 
  
* Test the multipliers (perform the following steps for each of the two multipliers available on the analog computer):
+
[[Category:Manual]]
** Connect the DVM to the output of the multiplier being tested.
 
** Connect the two inputs of the multiplier with +1 and +1 and check that the DVM reads very near to 1.000.
 
** Connect the two inputs of the multiplier with -1 and -1 and check that the DVM reads very near to +1.000.
 
** Connect one input to +1 and one input to -1. The DVM should now read very near to -1.000.
 

Latest revision as of 21:36, 23 August 2022

A closeup of a THAT in Minion mode with Oscilloscope probes attached.

The Analog Thing (abbreviated as THAT) is a high-quality, low-cost, open-source, and not-for-profit cutting-edge analog computer developed by anabrid under the brand Analog Paradigm for educational and recreational purposes. THAT will be available for sale at a net cost price of around €300. The component list, circuit diagrams and circuit board layouts of THAT are all Open Source. Information on how to build THAT from scratch and how to operate it can be found on this wiki.

Version 1.0: Specifications and Photos

The prototype consists of two main parts: A top PCB with gold-plated through-hole sockets suitable for 2 mm patch cables, and a base PCB, which contains the main electronic circuitry, the manual controls and ports for external connectivity. A Panel Meter mounted in the top PCB can be used to display coefficient values and, when the device is set to the repetitive operation mode, its operation time.

The size of the analog computer is 203mm x 240mm x 35 mm (with knobs).

Schematics

The schematics and bill of materials for the base board are Open Source and can be found here: [1]

The schematic of the FRONT PCB can be found here:

CAD and Gerber files

Under construction icon-blue.svg
This section is still under construction! Upload the Gerber files here
A first glance at the dimensions of THAT

The size of the PCB is 201mm x 240mm. The overall height (including feet and front panel potentiometers) is 38mm. The height of the two PCBs (without screws) is 16mm. Note that the base PCB has throught hole components, thus feets are mandatory (at least 2mm in elevation). The weight is approximately 900g including cables.

We have digital 3D Models of The Analog Thing in the wiki.

Instructions and further reading