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Andy56

Un pedal que no conocía, puesto a punto por Uncle Doug

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Acabo de ver este video (dura más de una hora así que lo vi a los saltos), se trata de un pedal de eco y delay en base a un disco anodizado de aluminio que funciona como material donde se graba la señal y después se relee, todo bajo aceite. Esto es de 1977 de Morley, un monstruo electromecánico increíble, vale la pena como curiosidad técnica, y vale la pena ver como el amigo Doug enseña como va deduciendo los problemas y los va resolviendo.

El efecto, mata por supuesto. El principio de funcionamiento es similar a los viejos osciloperturbógrafos, que se usaban en centrales y subestaciones eléctricas, antes que llegara la "inundación digital", que redujo precios y mano de obra especializada.

Que lo disfruten:

Salu 2

Andy

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A ese tipo de tecnología le dicen "oil can delay" (lata de aceite). Si mal no recuerdo  el aceite funciona como conductor. O sea, es un delay electromecánico.

Lo dejaron de hacer porque el aceite que usa es cancerígeno. Parece que en los ´60 y ´70 eso no les preocupaba mucho... 😲

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Lo ví, tampoco conocía el pedal. Tremendo.

El canal de Uncle Doug es mi favorito por lejos, super didáctico como explica todo. En esta cuarentena me pasé horas viendo sus reparaciones.

 

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Es un genio el tío Doug.. La verdad que es un pedal RARÍSIMO, el mecanismo hecho con una lata el cual sigo sin comprender en cuanto a diagrama.. ya buscaré más sobre osciloperturbógrafos y el "oil can delay" que menciona @Mostro.

Aparte un tierno con esas aclaraciones filmando el monitor con un documento de Word o como te muestra la conducta de su gatito rescatado Casey.

Edited by Perro Negro

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Buenisimo! Lo malo de eso es que cada 40mil km o cada 1 año le tenes que hacer el cambio de aceite.

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hace 1 hora, Perro Negro dijo:

Es un genio el tío Doug.. La verdad que es un pedal RARÍSIMO, el mecanismo hecho con una lata el cual sigo sin comprender en cuanto a diagrama.. ya buscaré más sobre osciloperturbógrafos y el "oil can delay" que menciona @Mostro.

Aparte un tierno con esas aclaraciones filmando el monitor con un documento de Word o como te muestra la conducta de su gatito rescatado Casey.

El osciloperturbografo funcionaba con un tambor giratorio y un papel encima con una pluma de escritura. Cuando hay un corto circuito en una de las líneas de alta tensión por ejemplo, la corriente eléctrica va aumentando y al pasar cierto umbral definido, la pluma apoyaba en el papel y trasaba la curva de crecimiento de la corriente y de esa manera se podía estudiar el fenómeno. 

Este bicho me hizo recordar a esos viejos dispositivos de monitoreo eléctrico.

En este pedal, se produce algo parecido, cuando lo accionás se graba en el disco de aluminio la señal de la viola y simultaneamente un captor toma la señal con lo que se produce  la repetición del eco, como en los viejos ecos de cinta.

El uso del aceite no lo entendí bien, tengo que escuchar de nuevo esa parte, pero me pareció que además de lubricar al disco, sirve para que el captor tome la señal en forma más pareja.

No soy experto en estos temas, pero por ahí @Alejandro Fourcade ve el post y echa un poco de luz....o algún Musiquiatra aficionado a estos menesteres....

Salu 2

Andy 

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hace 23 minutos, Andy56 dijo:

El uso del aceite no lo entendí bien, tengo que escuchar de nuevo esa parte, pero me pareció que además de lubricar al disco, sirve para que el captor tome la señal en forma más pareja.

El fucionamiento de este tipo de tecnología está explicado en Geofex.com. Como Geofex no tiene link directo a la página dentro de Geofex donde está la info, copio y pego acá (en inglés):

 

Before digital delays, before analog bucket brigade delays, there was an effects technology that subbed in for tape delays that was portable and relatively easy to use for floor mounted items. This was the rotating oil can delay, and here's how it works.

Everyone is familiar with magnetic storage - you move a substrate containing magnetizable particles past a recording head that has an alternating magnetic field in it. The magnetic field polarizes the magnetic direction of the particles on the substrate and an "image" of the magnetic field alternations is thereby stored in the particles. Reading is the reverse - you run the substrate past a pickup head with many turns of hair-thin wire and the magnetic field in the particles causes a voltage to be induced in the coil of wire, reading the info that was recorded.

There are usually "dual" operations for all magnetic and electronic operations, interchanging electric field for magnetic field and capacitors for inductors. This is no exception. If you put charge into a capacitor, it holds the resulting voltage, a crude form of storage. If you have many incredibly tiny capacitors, you can start making a fairly good representation of a varying voltage. This is in fact the way bucket brigade delay chips work.

There is another way to do electrical field storage. Insulating materials can be given an electric charge, as we all know. Just wear rubber soled shoes and walk across pile carpeting on a dry winter day, then touch a doorknob. The motion of the shoes across the carpet stored a charge on the shoes (and then you) that was expressed visibly and audibly when you touched the doorknob.

In a similar way, if we have a fine brush of conductive wires, and arrange an insulating belt to be moved past, just touching the brush, we can put a large AC voltage on the brush and some of the electric field will be captured on the surface of the belt. Since the belt is an insulator, the charge can't go anywhere, so the electrical charge forms a replica of the voltage on the brush. Each tiny area of insulating surface is in fact acting like a micro-miniature capacitor, storing the value of the voltage from the brush at the instant the brush moved away from it, just like the magnetic particles in a tape machine store a replica of the magnetic field from the record head.

The tiny voltage-carrying capacitors are carried off  as the insulating belt moves. The voltage would eventually leak off into the air if we let it. We can instead choose to keep it in a dry environment for a while, and "read" it later with a very high impedance amplifier. It turns out that vacuum tubes are ideal for both the writing (at high voltage) and reading (very high impedance) of such capacitive storage, and indeed the first oil can delays were tube based. Later as semiconductor technology got better, transistor and FET read and write amplifiers were made for the oil can delays.

So why the oil? What's that do? Remember that business about leaking into the air? The oil provides a sealable insulating layer over the insulating belt so the charge is trapped inside and has a hard time leaking into the air. The brushes reach right through it to put in/take out charge, and the voltage is protected from leaking away.

The oil is the center of a controversy - the original oil is reputed to be a hazardous material, carinogenic, etc. Is it? Maybe. The best insulating oils available at the time the oil can delays were designed were transformer insulating/cooling oils. These were definitely polychlorinated biphenyl based - the same "PCB's" that are now banned from all use as containing deadly dioxins. The only question is whether the oil can delay makers used that stuff or something else entirely. 

If you're restoring an oil can delay that is now dry, what oil do you use? I've heard of using mineral oil from a pharmacy, Singer brand sewing machine oil, even 20 weight motor oil, all said to work to some degree. However, the reports have been decidedly mixed.

I recently stumbled onto the Tel-Ray page (http://www.geocities.com/tel_ray/home.html) where some of my intuitions on oil can delays were confirmed, and where I found a reference to the original patents on the technology. You can look them up at the US patent office web site if you're interested. Look for US Patents 2892898 and  3072543. From what I read, we might be able to make new, functioning oil cans - they don't look like rocket science ( as old-hat as rocket science seems now, even ).

The principals in the Tel-Ray page have now confirmed some of my guesses, and have graciously extended the info a great deal. From the patents, it is clear that the original oil can delays were just as I guessed, capacitive storage devices. However, the second and third patents delve further into the lubricating medium. It seems that by carefully dinking with the lubricating/insulating oil and doping it with various things to get conducting particles spread out in the oil, you can make for a higher signal level stored in the rotating capacitor, and hence better signal recovery, lower noise, and all-round better performance. 

Zak Izbinsky, Richard Bills and Jamie Ray dug out the detailed info, as displayed at the Tel-Ray site. The "real stuff" replacement oil for the oilcan effects is Union Carbide "Ucon" LB-65 oil. It is not carcinogenic, and not PCB oil.

This is the exact same substance as was originally used by Tel-Ray in the 60's as specified on the third patent. It is still available through Union Carbide/DOW and is reputed to be only $200 a gallon. ... GAK!!!

However, the guys at Tel-Ray have helped out. They bought a supply and will parcel out just enough for your oil can for about $25. Check them out.

The second method

I've also come across a second method for "oil can" delays.  I put the quotes in because it doesn't use any oil. I got a Vox Echo-Reverb model V807 recently. It had a typical oil can delay... until I looked further. There's no oil, but not only that, it looks like there never was any. Multiple spring contacts are held against a rotating disc in a machined aluminum housing with a counterbalancing spring mechanism to keep them all just touching. It looks like this one is intended to get around the Tel-Ray patents. I'll know more when I get the bugs fixed and get it running.

 

R.G.

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hace 1 hora, Mostro dijo:

El fucionamiento de este tipo de tecnología está explicado en Geofex.com. Como Geofex no tiene link directo a la página dentro de Geofex donde está la info, copio y pego acá (en inglés):

 

Before digital delays, before analog bucket brigade delays, there was an effects technology that subbed in for tape delays that was portable and relatively easy to use for floor mounted items. This was the rotating oil can delay, and here's how it works.

Everyone is familiar with magnetic storage - you move a substrate containing magnetizable particles past a recording head that has an alternating magnetic field in it. The magnetic field polarizes the magnetic direction of the particles on the substrate and an "image" of the magnetic field alternations is thereby stored in the particles. Reading is the reverse - you run the substrate past a pickup head with many turns of hair-thin wire and the magnetic field in the particles causes a voltage to be induced in the coil of wire, reading the info that was recorded.

There are usually "dual" operations for all magnetic and electronic operations, interchanging electric field for magnetic field and capacitors for inductors. This is no exception. If you put charge into a capacitor, it holds the resulting voltage, a crude form of storage. If you have many incredibly tiny capacitors, you can start making a fairly good representation of a varying voltage. This is in fact the way bucket brigade delay chips work.

There is another way to do electrical field storage. Insulating materials can be given an electric charge, as we all know. Just wear rubber soled shoes and walk across pile carpeting on a dry winter day, then touch a doorknob. The motion of the shoes across the carpet stored a charge on the shoes (and then you) that was expressed visibly and audibly when you touched the doorknob.

In a similar way, if we have a fine brush of conductive wires, and arrange an insulating belt to be moved past, just touching the brush, we can put a large AC voltage on the brush and some of the electric field will be captured on the surface of the belt. Since the belt is an insulator, the charge can't go anywhere, so the electrical charge forms a replica of the voltage on the brush. Each tiny area of insulating surface is in fact acting like a micro-miniature capacitor, storing the value of the voltage from the brush at the instant the brush moved away from it, just like the magnetic particles in a tape machine store a replica of the magnetic field from the record head.

The tiny voltage-carrying capacitors are carried off  as the insulating belt moves. The voltage would eventually leak off into the air if we let it. We can instead choose to keep it in a dry environment for a while, and "read" it later with a very high impedance amplifier. It turns out that vacuum tubes are ideal for both the writing (at high voltage) and reading (very high impedance) of such capacitive storage, and indeed the first oil can delays were tube based. Later as semiconductor technology got better, transistor and FET read and write amplifiers were made for the oil can delays.

So why the oil? What's that do? Remember that business about leaking into the air? The oil provides a sealable insulating layer over the insulating belt so the charge is trapped inside and has a hard time leaking into the air. The brushes reach right through it to put in/take out charge, and the voltage is protected from leaking away.

The oil is the center of a controversy - the original oil is reputed to be a hazardous material, carinogenic, etc. Is it? Maybe. The best insulating oils available at the time the oil can delays were designed were transformer insulating/cooling oils. These were definitely polychlorinated biphenyl based - the same "PCB's" that are now banned from all use as containing deadly dioxins. The only question is whether the oil can delay makers used that stuff or something else entirely. 

If you're restoring an oil can delay that is now dry, what oil do you use? I've heard of using mineral oil from a pharmacy, Singer brand sewing machine oil, even 20 weight motor oil, all said to work to some degree. However, the reports have been decidedly mixed.

I recently stumbled onto the Tel-Ray page (http://www.geocities.com/tel_ray/home.html) where some of my intuitions on oil can delays were confirmed, and where I found a reference to the original patents on the technology. You can look them up at the US patent office web site if you're interested. Look for US Patents 2892898 and  3072543. From what I read, we might be able to make new, functioning oil cans - they don't look like rocket science ( as old-hat as rocket science seems now, even ).

The principals in the Tel-Ray page have now confirmed some of my guesses, and have graciously extended the info a great deal. From the patents, it is clear that the original oil can delays were just as I guessed, capacitive storage devices. However, the second and third patents delve further into the lubricating medium. It seems that by carefully dinking with the lubricating/insulating oil and doping it with various things to get conducting particles spread out in the oil, you can make for a higher signal level stored in the rotating capacitor, and hence better signal recovery, lower noise, and all-round better performance. 

Zak Izbinsky, Richard Bills and Jamie Ray dug out the detailed info, as displayed at the Tel-Ray site. The "real stuff" replacement oil for the oilcan effects is Union Carbide "Ucon" LB-65 oil. It is not carcinogenic, and not PCB oil.

This is the exact same substance as was originally used by Tel-Ray in the 60's as specified on the third patent. It is still available through Union Carbide/DOW and is reputed to be only $200 a gallon. ... GAK!!!

However, the guys at Tel-Ray have helped out. They bought a supply and will parcel out just enough for your oil can for about $25. Check them out.

The second method

I've also come across a second method for "oil can" delays.  I put the quotes in because it doesn't use any oil. I got a Vox Echo-Reverb model V807 recently. It had a typical oil can delay... until I looked further. There's no oil, but not only that, it looks like there never was any. Multiple spring contacts are held against a rotating disc in a machined aluminum housing with a counterbalancing spring mechanism to keep them all just touching. It looks like this one is intended to get around the Tel-Ray patents. I'll know more when I get the bugs fixed and get it running.

 

R.G.

Es medio largo pero está bueno, claro no es almacenamiento de la señal magnético (el aluminio no es material ferromagnetico como la cinta de los Echoplex por ejemplo), sino almacenamiento por campo eléctrico, muy ingenioso y complicado si lo pensás, después cuando lo ves hecho decís parece una boludez.......bueno nada, esa es la diferencia entre los soñadores y los creadores....

Gracias don @Mostro

Andy

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hace 4 horas, Mostro dijo:

A ese tipo de tecnología le dicen "oil can delay" (lata de aceite). Si mal no recuerdo  el aceite funciona como conductor. O sea, es un delay electromecánico.

Lo dejaron de hacer porque el aceite que usa es cancerígeno. Parece que en los ´60 y ´70 eso no les preocupaba mucho... 😲

Me cito a mí mismo porque lo que dije es inexacto, de acuerdo al artículo que copié: 

- El aceite en realidad funciona como aislante para que no se pierda la carga eléctrica del disco al aire.

- El aceite necesario para que funcione el pedal (Union Carbide "Ucon" LB-65 segun el artículo) NO es carcinogénico. Si lo eran otros aceites aislantes/refrigerantes de esa época, los famosos PCB (bifenilo ploriclorado) que luego se prohibieron. Cito de https://www.revistaei.cl/columnas/pcb-en-transformadores-un-contaminantesin-rumbo/# :

"La liberación del aditivo con PCB contamina el suelo, las napas y el agua, y el principal riesgo ocurre si los transformadores explotan o se prenden fuego, ya que en ese caso el PCB se transforma en un producto químico denominado dioxina y por lo tanto, según el Programa de las Naciones Unidas para el Medio Ambiente (PNUMA), es uno de los doce contaminantes más nocivos fabricados por el ser humano."

Como curiosidad busqué en E-Bay y se vende ese aceite para los pedales. 

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hace 37 minutos, Mostro dijo:

Me cito a mí mismo porque lo que dije es inexacto, de acuerdo al artículo que copié: 

- El aceite en realidad funciona como aislante para que no se pierda la carga eléctrica del disco al aire.

- El aceite necesario para que funcione el pedal (Union Carbide "Ucon" LB-65 segun el artículo) NO es carcinogénico. Si lo eran otros aceites aislantes/refrigerantes de esa época, los famosos PCB (bifenilo ploriclorado) que luego se prohibieron. Cito de https://www.revistaei.cl/columnas/pcb-en-transformadores-un-contaminantesin-rumbo/# :

"La liberación del aditivo con PCB contamina el suelo, las napas y el agua, y el principal riesgo ocurre si los transformadores explotan o se prenden fuego, ya que en ese caso el PCB se transforma en un producto químico denominado dioxina y por lo tanto, según el Programa de las Naciones Unidas para el Medio Ambiente (PNUMA), es uno de los doce contaminantes más nocivos fabricados por el ser humano."

Como curiosidad busqué en E-Bay y se vende ese aceite para los pedales. 

Si, trabajé en fábrica de trafos de potencia y ya desde comienzos de los '80 que se empezaron a prohibir los PCB, que en realidad en los '50, habían sido una solución al riesgo de incendio de los trafos de aceite mineral, porque tenía un punto de inflamación más alto que los aceites minerales comunes.

Es todo un tema con el que cargamos los que trabajamos en la industria eléctrica......

Salu 2

Andy

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De esta línea de pedales todavìa conservo un viejo Wah Morley, de los primeros, a 220 y sistema òptico con sensor, super precario  y simple de setear.

Suena que es la gloria. Decí que es una zapatilla de acero y pesa la mitad de cualquier pedalboard. 

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