Wednesday, 18 August 2021

Todgha Gorge in Morocco

 These are some pics from the Todgha Gorge in Morocco
 

 
 They  are a series of limestone river canyons, or wadi, in the eastern part of the High Atlas Mountains in Morocco
 
The height of the canyon walls can vary, but in some places can be up to 400 metres (1,312 ft) high..
 

 
 
The Todra Gorge is about 15 km long.
 
There is alot of trekking involved..


 



 






 Oasis in the distance..


 



 

 
Tinerhir is the capital of Tinghir Province  
 
 

 
Its a good place to base any trecking of the gorge from.
The city of Tinghir (jamaate tinghir) has a population of 42 ,000
 
 
The city is at the center of one of the most attractive oases in southern Morocco. 
 

 
 
Lush palm trees cover about 30 miles (48 km) on 500-to-1,500-metre (550 to 1,640 yd)-wide tracts along the Wadi Todgha.
 

 
 
 
 
 
 
 
 

Sunday, 15 August 2021

NLC Choral Generator - Build notes - part 1

 Some build notes for the Choral Generator.


This is quite a big module - 18hp
It's a BBD based triple chorus generator.
It is inspired by the Choral generator in the ARP Omni.

it can be used to process CVs as well as audio.

 
 
 
 
 
 
 
 
 
 
 
 
 

As is, a signal patched into
in 1 will be fed thru all 3 BBDs and arrive at out all, so the 3 BBDs operate in parallel as is done on the ARP Omni. The best effect is to modulate them with a 3 phase signal (I guess I better make one) or signals from a quadrature oscillator such as the NLC Feague.



V3207 - this is a cool audio BBD chip.
You need 3 of these
Its a clone of the MN3207

Description

The V3207 is a 1024-stage low-noise, low-voltage BBD analog delay line that provides analog signal delays of up to
51.2 ms and is particularly suitable for the generation of sound effects (reverb, echo, phaser, flanger, etc.) in audio equipment such as karaoke microphones, guitar effects pedals, etc.

2. Features

• Variable Delay of Audio Signals: 2.56 ms ~ 51.2 ms
• Wide Supply Voltage: 4 ~ 10 V
• Wide Dynamic Range: S/N =73 dB typ.
• Low Distortion: THD =0.4 % typ. (Vi = 0.25 Vrms)
• Clock Frequency Range: 10 kHz ~ 200 kHz
• Package outline: DIL-8 (V3207D)
• ROHS compliant (PB-free)




I decided to buy some MN3207s from ebay.
Are they genuine???

The 13700 op-amp


The three 40106  schmitt triggers

 


The three Jfets -- MMBFJ309 FET

 
Voltage regulators



To be continued...

Wednesday, 11 August 2021

building of the Klee sequencer - part 2

This is part 2 of my building of the Klee sequencer
The Klee is a classic sequencer.
Sometimes referred to as a "shift register sequencer", the inspiration is from 2 sources I understand:
Don Buchla's 266 SOU and Ken Stone's Gated Comparator. 
The Klee circuitry was designed by Scott Stites and uses two CD4034s as its shift register.
It's design has been adapted to Eurorack , 5U MOTM, 4U Serge & Buchla  formats.
 
Other modules such as the turing machine & the noise ring also use a shift register.
These are worth exploring.

Part 1 and 3 are here

It's not a difficult build. Just a long one.


-------------------------------------------------------------------------------
The lower mother board is made up of a digital and an analog side.

Digital side now
 
 
R71-R78 --- do not install anything in these positions (leave them empty)
These are marked with a *


100K resistors first
There are 24 of these. 
They are 1%, 1/4W
R 23 TO R26, R30, R49, R52 TO R62, R81 TO R84, R89, R90, R94

 
 
 
 
 
 
 
 
 
 Metal Film Resistor 4.7Kohm 1%
R31, R48, R85 TO R88 
and R32 TO R47   these are the sixteen 12V LEDs ?




 
 
 
 
 
 
 
 
 
 
So what's the difference between a Klee and a standard sequencer?
As mentioned earlier ... this uses bit shift registers.
A standard sequencer can only have one step active at a time, but a Klee can have many active steps.
If more than one bit is active , the slider values will be summed.
 
 

R91 - bom says 270K
Was supplied a 270ohm 
I'll use a 270K resistor in the build.



 
 
 
 
 
Film Capacitors 100volts 1000pF
Six of these - C6 TO C10, C18


The 22K resistors ... there are 25 of these according to the BOM however they aren't numbered.
Through a process of elimination, the resistors are
R1 to R22, 50, 51,80. These are all 5% tolerance, 1/4 W
 



 
---------------------------------------------------------------
Back to the Analogue Board
It is the source of the signals required for the Variable Range control options. It is also the board that directly interfaces to the power supply, and the board that involves all of the calibration of the Klee. 
 
Dont install this trimmer (R41) on the analog section of the mother board.
If any of the variable range options are installed, then you should refrain from installing R41. The front panel Variable Range Control will take over the function performed by that trim pot
 
 
I accidently installed the trimmer, and had to remove it later

 
-------------
 

 


It's time to install the ICs
The OP amps of the Analog board first
  .. 072 & 074s



Note W2.
This is a jumper. 
W2, is only installed if any of the variable range options are not installed. 
 
(Note that if you are using the older build manual they will mention jumper W1, which I can't see on this Euro board... W1 should only be installed if the power supply, for some reason, has only one ground connection.... as is the case with Eurorack. In other words, if you have a power supply with only one ground lead, install W1. This ties the analog and digital grounds together at this one point).


J16
J16 provides the signal(s) to the front panel Variable Range control(s).
In the old build manual, you needed to put a jumper here I understand.
The manual for the Euro-Klee  says
"You do not need to install any of these jumpers – it’s all taken care of on the daughterboard."





The CMOS ICs - CD4051, & 4066 x 4

------------------------------------------
The digital board

CD4071 - U3, Quad 2 Input OR Gate
CD4013 - u5 , Dual D Flip Flop
CD4053 - Quad 1 of 2 Switch -  multiplexer - u9
 




CD4093 Quad Schmitt Nand Gate x 3
 U4, U12 – U13
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
LM358 Dual OpAmp x 2.... U1, U8
 
 LM324 324 LOW POWER QUAD OP-AMP IC x2
U14, U15
 
CD40106BE Hex Schmitt Trigger x 3. U2, U10 – U11
 
Transistors 
Only one type of transistor is used throughout the Klee Sequencer – the 2N3904 NPN transistor, and they’re all located on the Digital Board. These transistors are used to drive the clock, reference and gate bus LEDs. There are six of these transistors.

CD4034 x 2.... U6 & U7
they're 8-Stage tri-state bidirectional parallel/serial input/output bus registers
 
 The board is pretty much done.
Now time for the headers
 

----------------
 
Putting the headers in is a fiddly process.
Here is a list of the headers:
Analogue Board: SIL Pin Rows --- J1, J3, J5, J6, J7, J8, J10, J12, J13, J15, J16 
                            MTA Headers --- J2, J4, J9, J11 (not placed in 2015+) 
Digital Board: SIL Pin Rows --- J2, J4, J5, J8, J9, J11, J12, J13 
                             MTA Headers --- J1, J3, J6, J7, J10 (not placed in 2015+) 
 
 

I like to line up 4 at a time and solder, then pull the boards apart and reposition 4 more.
 


Eventually, the boards should look something like this

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

This is the top of the daughter board.
It holds the switches, sliders, pots, LEDs etc.


Some of the sliders sit on top of some of the headers we just soldered.


Socket pin shaving time to decrease chance of shorts ..
TRy to cut them as close to the PCB as possible to avoid any shorting.
Ive added some electrical tape as well
 
To be continued.......



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Monday, 9 August 2021

Valley D'Agdz Morocco

 Agdz, also spelled Agdez is a Moroccan town in the Drâa-Tafilalet region, in the Atlas Mountains 
 
 
 These are pics taken of the outskirts. The valley is desolate but so atmospheric.
 
 
This is the Entrance of the Drâa Valley



 

 
 Agdz lies at the feet of Djebel Kissane and along the shores of the Draa River.
 
 



Located on the old caravan road connecting Marrakesh and Timbuktu
 




 
 
Agdz, which means “resting place“, is a well deserved name