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Ace Tone FR8L recapping and external psu, trigger mods

Assorted pics of the actual boards.. might be useful to someone.

That good old recappin’ blues:

Since one of the boards was GLUED to its standoff, i had to solder some caps on top of the older ones.. now one of the caps had leads so short i thought it might be useful to remind myself where does each lead went (see pic w scribble).

And the odd freaky transistors that didnt have its legs cut off (and indeed they were perilously almost touching)

The FR8L can produce 13 drum sounds-and very crispy too, thats why i decided to modify it..

Circuitbenders.co.uk’s trigger module: wires aplenty, but this will allow me to trigger each drum sound from a midi to trigger highly liquid board, that has been assembled back in the day to control my fr3-a build/mod and brilliantly carried out by circuitbenders.co.uk (you can see it HERE and HERE TOO).

The trigger board for the fr8l can be ordered HERE but remember, stock is limited.

Please note a male/female hex spacer (m3 22mm) is needed to screw the trigger board to the existing hex nut.

I decided to put the trigger input jacks in an external box-lots of fun soldering all the tiny jacks!

External PSU mod:

From an idea by circuitbenders.co.uk

READ ABOUT IT HERE

Due to the nature of the machine it is best to reduce background noise as low as possible-and an external power supply may be a better power source than the provided transformer since the filtering in the power supply section is basically nil.

I had to make a quick mod here so if you may, bear with the crudeness of these connections-i was also low on cables so pardon the lacking colour scheme..

Remove the transformer (WARNING: Dangerous voltages around this area)

First of all take a nice picture or two of where the transformer cables were originally.

The plastic thing where the red orange and black wires go is a diode bridge-check the schematic from the FR8L service manual, it has to be removed along with the transformer. We’ll reuse thosw wires so just cut them and leave them hanging for now.

Then when everything has been unscrewed and cables cut, make a bridge connection between the two pins of the on off switch at the tagboard end (pink cable).

Red and orange cables soldered to the positive side, grey cable connecting all black leftover cables to the negative side.

To attenuate noise from using a switching psu i put a choke in series with the positive pole, and a 2200uF 50v capacitor in parallel between + and – like this:

Remember the resistor between + at the psu and the orange cables (you can barely see it in the picture because i used some spare shrink tubing to prevent shorts).

🙂

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Novation SL Zero mkII Editor – uploading – saving template

Since all the download links seem to be down and this product is not supported anymore by the folks at Novation’s, i thought i’d share with you a link where you will still be able to download the (beta version, please note all the apt disclaimers that apply to betas) SL Zero MkII Editor program, that will allow you to program a template for the midi controller (this is not the Automap program, mind you).

Click here to download the Editor software

…hoping Novation will not take down this link too…

And a quick video on how to upload your template from your pc to Novation’s controller-no fancy stuff.. no screen capture sorry-phone shot. Rough and ready. It’s more of a reminder for me on how to do it lol.. personal reference.

Here:

Altec 1592B repair, 1588B module, XLR pinout output etc

Recently i got a nice Altec 1592B mixer.

Each input requires a dedicated preamp/transformer module, for microphones there’s preamp, 1588B or preamp+12v phantom power, model 1588C.

I had to do a massive recapping job on the 1592B- the original caps values were all over the place-and i mean not only electrolytics-the only ones that were still measuring ok were the tropical fish and some of the lower values disc caps- though most of the electrolytics were good quality, Mallory or West Germany made, ROE (Roederstein). I replaced them all with Elnas (they seem to be the standard nowadays).

Also, the resistor after power transformer 7818 (that feeds part of the tone section, so if you have an unit that powers up but does not produce a sound, check for +18v at pin 6 of the tone board, that is linked to the power board after (out) the aforementioned 7818) was burned-clear sign that some damage had taken place. The schematic calls for a 10 Ohms resistor-i decided to put a 100 ohms substitute, much better.

Sounding good, i decided to recap also the 1588B module i have here (more are on the way, and when factory new, they were fitted with 3 modules).

After using a small screwdriver to pry the enclosure open, i took a look at this interesting blog (check it) for the schematic-i also took the time to sub the carbon comp resistors with metal film and yes-noise went down.

For your reference, here’s the resistors network:

Q1 and Q2 pinout:

Troubleshooting:

If the preamp is not working, check carefully the resistors-they break easily. One immaculate looking (inside and out, the spongy filler still in good soft condition, no leakages on the plastic screen etc) 1588B i have had a resistor broken at its base, and since the components are so squeezed together it was impossible to see it-i decided to test the transistors (thats why i took the q1 and q2 pics above) since everything was looking proper-and there-i spotted the broken resistor! The preamp would still burst in noise if i knocked the mic gently on the capsule, yet it wont amplify it properly. Thats the resistor connected to ground on the white wire-a pain to desolder too.

If you must desolder stuff, be patient-these boards wont take a 300 degrees hot iron-the circuit tracks will lift if you heat them up too much-use care.

Since someone over at the Tape Operator forum has raised the warning that the power supply may have been ill designed, i am powering it using an external psu (using the battery option), 24v dc.

Terminal: from left, my battery (external psu) connections (- and +) and pinout to wire an XLR balanced jack to the output: hot, cold and ground… in the mess between high and low impedance i went with, 600 ohms, good for any mixer or recorder input. PLEASE note 2 and 3 terminals are bridged (connected) at the terminal post. The signal is nice and strong.

I will not mod this unit, i like it as it is. Nice and retro sounding.

TR707 TR727 reset, midi out, tricks etc

Reset your TR707 or TR727 to factory settings.. here is the buttons combination to give your drum machine a fresh new start and to check leds and screen, buttons.

Keep pressed CLEAR and INSTRUMENT/GUIDE and switch on the legendary (yes, legendary) drum machine.

All the lights will turn on, then step leds will blink one by one.

After the light show, press ENTER/CARTRIDGE to proceed with the screen test.

Press the buttons and see the relevant dots show up on the screen.

Switch off.

How to use the TR707 or TR727 to output midi notes, and use it as a midi controller to play other midi modules, samplers (bear in mind its defaut midi channel is 10):

STOP the pattern/track if it is playing.

Enter TRACK PLAY mode.

Holding SHIFT press INSTRUMENT/GUIDE and MIDI CHANNEL.

This procedure will mute the instrument’s internal sounds but will allow you to control external gear using the TR707 or TR727.

To revert back to default, using the internal sounds but NOT transmitting midi notes, and if you have a TR707/727 that is silent, just use the same keypresses again.

Common troubles with these machines:

PSU jack fail, power transistor 78M05 (can be substituted with 78S05), power supply section electrolytic caps.

Dim screen=check the power supply section.

Try different psu transformers too: Roland’s own are recommended, etc

These are machines that heal themselves.. put them aside for a while or leave them turned on for some time and they will fix themselves.

Maybe.

Roland CR8000 buttons repair made easy

Roland Compurhythm drum machine CR8000 with faulty or worn buttons.

Sounds a lot like the TR808, but a design fault makes these buttons useless after a while.

You will have to pull the plastic covers first, to reveal the spring and rubber dome under which we will drop a bit of conductive paint..

To pull the plastic part you need to push the sides using a screwdriver or two like on this video:

Youtuber The Imp Of The Perverse has made a few vids of his restoration-he used my method too, check them

SammichSID Novation Zero SL mkii template

Those geniuses at Novation shipped this controller with a couple of software disks but alas, no TEMPLATE EDITOR for people who dont use a pc to make music.

Download the template editor program from their support pages, connect the Zero SL to your pc via usb, switch it on and fire the software. Press Global options on the SL, choose mem protect off.

Load the syx file provided by yours truly:

Masuto’s SammichSID template 😊

and then.. select

Press Write, and bob’s your uncle.

I saved it in location 20 (empty) and made it the startup template.

To use the drumpads to send cc (mod depth 1,2,3,4,5,6) on the novation zero SL you must first press REVIEW and then use the drumpads-you will see their assigned value increasing because we are using them as step switches.

For your reference, heres a crudely PAINT assembled wildcard:

Happy knob twiddling!

Akai S612 sampler

I opened my newly acquired Akai S612..to check for spiders and animal residue from its previous owner – i was intrigued by the “cassette interface”. Mine was screwed behind a closed metal door.

I realized right away it is the same cassette port as the Commodore 64.

And yes, you can save, verify and load your samples using an old (non)trusty tape Datassette!

I sampled a sound, got some tape to record, went fast forward 004 counts on the tape counter, pressed rec and play and then pressed save on the Akai panel. Red light, it’s recording.

Counter reading 044, the Datassette automatically stopped. I rewound the tape, switched off the Akai (remember with these old machines it is better to switch them off before plugging or unplugging devices from serial ports..), on again and Load. Pressed play on tape, and yes. It’s working. Easy.

No need to buy the MD280 rack to load discs on the S612.. you just need a Commodore Datassette (clean its heads and fix azimuth before doing anything)!