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701 Mod to standard toggle power switch .01 uf cap

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701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 13 Oct 2017 11:50

trying to figure out how to bypass the stock switch and rerout the incoming power leads to a standard on off toggle switch and I'd like to know what this .01uf cap is doing and how to wire it in with the 3 tab on/off switch...

Can anyone confirm if this is correct?

1 (2).jpg



on/off switch would like to use
ss.jpg











stock arrangement
2.jpg







thanks in advance
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 14 Oct 2017 01:09

here is the stock on/off mechanism in action.
https://www.youtube.com/watch?v=JyHaA2B ... e=youtu.be

what I don't understand is how the power can stay turned on when this little magnetic switch is momentary. It seems at least right after turn on the little magnet pulls away and turns off again? That is my main issue in understanding, along with the use of the .01/1000v cap. If I knew what the cap was for, I could rationalize backwards and try to work it into a toggle switch.....Full search here and on web doesn't seem to tell what that cap is for?




but regardless, I now believe that switch i wanted to use may not work, as it is a SPDTSingle Pole, Double Throw .

I believe that cap may be some suppression cap perhaps and it only needs to be 'on' at the moment of 'turn on' ? If so, I will need a different switch...

DPST

Double Pole, Single Throw

Dual ON-OFF

A pair of on-off switches which operate together (shown by the dotted line in the circuit symbol).


this may be the next best guess as to switch type:
A DPST switch is often used to switch AC electricity because it can isolate both the live and neutral connections

am still researching, if anyone finds this and can help would be much appreciated....
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby dualcan » 14 Oct 2017 16:04

Hi,
It seems that you are not understanding the mechanical switching process as used in all the older (pre 1982) Dual units. These power switches are all spst, mechanical (not magnetic) flip-over. To understand the basic working principal of these switches, it is advisable to read the service manual for these units, before attempting an outboard fix, which can be a dangerous (electro-shock) undertaking if carried out improperly.
As for the noise suppressor cap, these are simply placed over the two switching points, and buffer the back EMF created by the switch.
Regards,
k
Klaus Adlhoch, fmr. Assistant Service Manager,
Noresco -N.Q.I.-Dual of Canada,
Area of expertise: Tech Training and Consumer Service P.R.
Associated with Dual till Thompson era.
Favorite Duals: TG 12a, 1009, 721.
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 14 Oct 2017 23:21

thanks klaus, I've looked over the service manual and as having no EE degree, alot of it is over the head but the only section I found dealing with this on/off mechanism is shown below. I suppose on the schematics (which I cannot read) more is shown....but I've done this switch on a Lenco and an AR with no issues as their mechanism was not as complex as the dual's it seems. I will continue to look into it, as I'm committed to this becoming a reality ....the reasons are, the constant stopping and starting after each lp flip or swap totally ruins the lp experience. What I need is basic constant platter turning and I manualy shut off after complete listening session is over. Also the ground pin on that plastic switch box is broken off.

I figure it is simply a case of getting the correct switch (I assume you mean a SPST will work for this new arrangement?) and joining the AC in with the two blacks that come from the transformer section on one set of tabs and now based on your other suggestion, the cap goes over this same set of tabs? and it's a done deal?
2017-10-15 03_59_09-Greenshot.jpg


or is there more to it I am wondering....because I'm still left with that ground black wire that seemed to connect to that little magnetic (are you suggesting that is not magnetic is another question) switch and I don't know what to do with that ground. But still I need to understand how the stock switching works I agree/admit, and why to me it seems momentary. But obviously it is not, as once powered on the table stays turning until that switch is activated again via either a manual stop or an automatic mechanism. Your phrase, mechanical (not magnetic) flip-over, is new to me in describing what happens in a basic SPST switch, as flip over suggests momentaryness when I know that the switch simply as two positions and only 'flips over' when a person flips the switch. That is why in the stock switch I would have expected the little magnetic 'flapper' to have stayed in contact when 'switched on' and not quickly snapped back. but as you point out, I clearly am missing something...in any case, I thank you for the hints and will persevere into it....


2017-10-15 03_18_43-Greenshot.jpg





this is the only schematic I've found yet, it is of the motor itself, but in the lower left corner is possibly the switching mechanism>? at least that is where AC comes in. But due to lack of knowledge on my part, and the words being in german, I cannot literaly make no sense of it...
2017-10-15 03_48_39-Greenshot.jpg




so the objective is to translpant this to a single SPST switch is what I am now searching for? What I know is the two blacks from tranny area will couple with the left two incoming AC via the plastic switch, which are the two left vertical posts in the old switch.. In the new spst they will each meet on either end of switch. The cap same. Is the last black ground on the old plastic coupler (the last to the right in old switch - broken off),now not needed or routed elsewhere is a question....Also that .01uf/1000v cap is directional. I don't see how to accomodate that directionality on a spst switch. This is the 'shock risk' klaus mentioned?
2017-10-15 04_00_52-Greenshot.jpg
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby DSJR » 15 Oct 2017 11:36

Ummm - the start up time for this platter-motor assembly isn't instant I accept, but by the time the arm is off the rest, cued up and lowering onto the record, the platter is at speed and takes a while to run down when power is disconnected. Even in a hurry to change records, I've NEVER been caught out with the platter not yet being up to speed.

The only reason we used to suggest leaving a Rega or Pro-ject deck running all the time during a session is to prevent extra stretching stress on the fragile belts they use, no other reason...

The 701 is a lovely thing and best not butchered in my experience and opinion. If you don't like the way it functions, buy something else - yesterday on the Harbeth Facebook page, I saw a lovely largely original Lenco GL75 with a retro-fitted S shaped black Jelco arm (250 model?) fitted and this even uses the original GL75 cueing device, so no nasty carve-ups needed at all! Remember, the 701 is around forty five years old now and some caps on the motor board will need replacing (all in threads here). The mech is very quiet and gentle indeed (low operational drag on the drive) and doesn't *seem* to jam or get sticky (Klaus may disagree). The main bearing is properly heavily lubricated with a special grease from new, so should NEVER need touching - the grease in mine is fine in texture and amply lubricating the thrust assembly, so left alone.

If you've found a 701 very cheaply, then it'll be an appreciating asset if left original and not butchered in any way. Europe seems to appreciate this value if not other markets as yet, but they will...
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 15 Oct 2017 14:03

fair enough, but I'd like to continue as a brain excercise. ever since suffering a concusive explsive in the gulf, my mental faculties have never recovered. It is very hard to learn new information and projects like these are the best rehab my doc says. So to understand how the switch works and theoretically, if one wanted to swap in a toggle switch in place of the stock switching, how would it be done.....

back to my concern regarding the cap. If it in fact is directional, I need to determine + and - somehow? (or is that cap a directional cap but is not needed/functioning as a directional cap? I believe sometimes due to stock availability sometimes a directional cap is used even though it is not needed. the answer to that question may change the location of the cap legs, but can anyone suggest if this diagram is any closer to the truth?

2017-10-15 18_02_18-Greenshot.jpg
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby dualcan » 15 Oct 2017 21:03

Hi,
In your previous post you mentioned:
I've looked over the service manual and as having no EE degree,

Just to set the record straight, neither do I have a degree other than an electronics course as a technician and that was completed in 1967...
Let's look at the power routing a bit closer though. You will find that the AC power to Garrard, BSR, Dual and many other early phonographs, was an interconnecting plug and socket named AMP-Molex. The wiring inside these plugs are standard and work with all the units using these AMP-Molex connectors. The AC cable that came with your old 1015:
1015f.JPG

is actually compatible with the 701, but let's examine in detail first!
The AMP-Molex plug and socket was normed with the following pin numbers corresponding to AC power routing:
MOLEX AC  pin- outs.JPG


Pin one is always chassis ground;
Pin two is AC power "hot", meaning that it goes to the SPST or single pole, single throw, power switch.
Pin three is power return. This is AC hot power, taken after the power switch. It serves to control power (on and off) supplied to the motor or transformer, and to internal (mounted within plinth) preamp, which back then was also 110/220 volts. Power for a preamp therefore comes from pin 3 (switched AC) and pin 4, AC common.
Pin four is AC power "common" and goes directly to the motor (1015) or the power transformer and strobe light of the 701.
In that picture we can see a new black power box which combined the motor wiring and Molex plug into one. The same old 1015 AC cable can be plugged into that new power box:
Dual 1214 power box.jpg
Dual 1214 power box.jpg (104.91 KiB) Viewed 141 times

In this picture we can see the same old cable inserted into the newer combined power plate (white rectangle). The green circle (pin 1) is again ground, directly to chassis.
Pin two goes to switch (yellow line) and to the noise suppressor cap, The "hot" power (red circle) enters here to be switched. Note: The actual switch is hidden from view, under the red cap in this picture.
Pin three is connected to the other side of the switch (yellow line) and the other side of the noise suppressor. The noise surpressor as seen, was an early semko paper capacitor of 0.01 uF value. The values can change on different models. These are never polarized caps (+/-)! Today, safety regulations insist on safety rated X2 or Y2 capacitors which will not catch fire essentially.
Pin four sees the common AC junction where the load (AC motor or transformer) is connected directly. Input is again the red circle (from Molex plug).
This power plate was changed just slightly for the 701 generation but pin numbers and operation is identical:
701 power switch.JPG

In this picture I'm cleaning the contacts of the power switch with a relay file which is akin to 1000 grit sandpaper. The ac supply cable is removed for easier service, but we can see that the strobe light cable on. following what we saw previously, the strobe sits on pins 3 and 4 which is exactly the place where the preamp was connected in the very first molex cable setup.
For the 701 nd some others, the AC wire is clamped onto the pins two and four:
KS3 ac power connector and switch box switch .JPG

and as can be seen was used in many other units.
For the 1216 for instance, the power box cover was open to let the Molex plug enter exactly on pins 1 to 4. The 701 has the cover top closed and uses a cord with clips, which clip onto pins 2 and 4, exactly like the very first set up.
Note: my description of Hot power and Common power are interchangeable since the AC plugs are not keyed on the plug. It is simply a description of the two AC leads.
We'll look at the 701 a bit closer in my next entry, but keep all the AC switching in mind!
Regards,
k
Klaus Adlhoch, fmr. Assistant Service Manager,
Noresco -N.Q.I.-Dual of Canada,
Area of expertise: Tech Training and Consumer Service P.R.
Associated with Dual till Thompson era.
Favorite Duals: TG 12a, 1009, 721.
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby dualcan » 15 Oct 2017 22:58

On this 701 diagram, similar to the one you posted:
701-1 with upgrade.jpg

I changed it to only show how the AC power:
701-1 with upgrade.jpg
701-1 with upgrade.jpg (50.99 KiB) Viewed 132 times

relates to what you actually see on the chassis:
701   chassis.JPG

In that drawing I removed the Strobe parts and all the servo electronics for the motor. What you do see is the encased black metal box with the two (gray) 22 volt wires going to the motor and the wiring from the AC plug going into the power switch box via the pins as noted in the earlier posting. The red capacitor (missing in the original drawing) is also inserted. Now the AC section of the drawing hopefully makes more sense.
To reiterate some items-
The safety caps are non-polarized and should be safety rated X2 variants. These are always placed across the power switching points, pins two and three.
The single pole single throw type switch used in all Duals, is always switched by either the cam set in motion (Start pressed) or tonearm being moved towards the record, for the older 1000 series via "Manual" selection on switch lever with arm off the rest post.
The power routing is for all the Molex type junctions identical as per pin locations.
Hope this helps to explain somewhat,
Regards,
k
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Noresco -N.Q.I.-Dual of Canada,
Area of expertise: Tech Training and Consumer Service P.R.
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 16 Oct 2017 04:15

thank you so much for this summary lesson,, this will take several days to comprehend and digest.....but already at hour 2 a migraine headache..frustrating, but I can see there is an answer to my questions in the above layout, perhaps once I learn what common really means in electricity because as of now I've no working understanding of common and I think a big part of my understanding is because of that . Will look into it more...thanks again.
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby dualcan » 16 Oct 2017 06:42

Hi,
I used the term AC hot and AC common for the two wires that are connected to the AC plug. Since the electric plug can be reversed when plugging into the wall socket, the term hot an common are interchangeable.
The actual house wiring to the AC outlet does however have a hot wire which is black and a common white (also referred to as neutral) wire.
The hot (black) wire comes from the fuse panel's breakers. The common or neutral (white) wire, starts from your water pipe's or natural gaz pipe's heavy copper cable which goes to the fuse panel. The white common wire is therefore grounded via the water or gaz pipe, since they are sticking in the earth- hence the term common or neutral.
In North America this household wiring is called a single split-phase wiring because we split the 220 volts that comes into the house via that grounded water pipe into two banks of breakers in the panel, each bank has 110 volts. The 220 volts is used directly in the kitchen range or sometimes the dryer and hot water tank.
Hope this clarifies the terminology a bit.
Regards,
k
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Noresco -N.Q.I.-Dual of Canada,
Area of expertise: Tech Training and Consumer Service P.R.
Associated with Dual till Thompson era.
Favorite Duals: TG 12a, 1009, 721.
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 16 Oct 2017 16:10

thanks, yes this has always confused, how older pre 70's era electronics did not have a ground or specify a true 'hot'....after researching many sources, my summarized takeaway.....

ground and neutral are closely related. However, the neutral and ground wires serve two distinct purposes

neutral wire, formally, called the “grounded conductor” provides the return path (for the current that is provided by the hot wire.) and is the wire that the electricity flows through once a circuit is completed, such as when you plug something in. It has no electricity flowing through it until electricity is flowing through some device and back out to your circuit breaker. Ground and neutral/common are bonded together at the main service panel/buss bar only and at no other point within the building wiring system, and therefore have the same electrical potential

The ground wire, on the other hand, will hopefully never have electricity flowing through it. It's only there as a safety mechanism: if, for some reason, electricity escapes (a hot wire -either hot or neutral- comes loose inside a device. That's why the ground wire is attached to the metal casing of devices so that if electricity is going into the case for some reason, it'll harmlessly flow through the ground wire to earth since electricity will always follow the route of least resistance and copper/aluminum has a much lower resistance than the human body. Without an earth wire connected to complete the route of least resistance to earth, the human body will conduct the full load current to earth if you should touch the live metal of faulty equipment.

Hot is any conductor connected with an electrical system that has electric potential (relative to electrical ground or neutral) which provides a 120 VAC current source. Regular two-prong plugs which lack the ground prong, can be connected with either prong on the hot side. A polarized receptacle - neutral prong is wider than the hot prong - keeps track of which wire is hot and which is neutral.



So, now as it applies to the 701 modification scenario, all that is important is to distinguish the two hots from the ground. Do not need to distinguish between the two hots (true hot and neutral/common).....

need to take a break but next I will try to understand whether the 'turning on' of the device via power switch is a result of shorting the two hot's to each other or one of the hots shorted to the ground. I suspect the answer is partly or wholly contained within the above information but as of yet it hasn't sunk in. Will revisit the pics you've provided, use some logic to work in reverse and combine it with the above info and I think the switch will make more sense....thanks again
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 18 Oct 2017 06:33

2017-10-17 22_26_02-Greenshot.jpg




This is beyond frustrating. I've got this diagram worked up but cannot complete the last wire from spst. The problem is I just cannot visualize elctricity, In what form it comes from the wall, what it does in the turntable and how it 'exits'..at the risk of exhausting patience klaus, could you give a quick 'common man' wording of what the electricity is doing when it exits the wall and makes its journey through the 701, in this case? ...for example, "the electricity comes from a power station to the house. at the all outlet it is split into two halves, both halves enter the turntable and immediately both go to a spst switch. one side goes to motor, awaiting a closed circuit whereupon it will start turning, the other side meanwhile went to the transformer awaiting the 'closed ciruit' signal. When the switch is turned on, X circuit is closed and z happens, when the switch is turned OFF, Y happens" ...or something like this. This is how my mind is trying to understand the process and it is not working for me because I still lack and understanding of the form electricity takes and how it moves. I know it needs a closed circuit to move however,. I have never understood how people who understand electricity, visualize the current coming out of the wires and into a component (stereo component). I guess I am trying to view electricity as a plumber would visualize pipes and water. It is similar but water is not broken into two halves which require a closed connection before it moves, so plumbing is much simpler for me to comprehend!...I will continue to mull this over and I know the answer is contained in the block diagram /schem below but i just cannot understand those lines either...very frustrating. Once I learn this though I think it will really all start to make sense.....
dual 701.jpg
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby dualcan » 18 Oct 2017 21:51

Hi,
The problem is I just cannot visualize elctricity, In what form it comes from the wall, what it does in the turntable and how it 'exits'..at the risk of exhausting patience klaus, could you give a quick 'common man' wording of what the electricity is doing when it exits the wall and makes its journey through the 701, in this case?


The same thing vexed me in my studies way back when the earth was flat..
I liked things that can be seen, so I interpreted electricity in a graspable form.
All my studies talked of circuits which were baffling in the beginning so I looked at it differently. Here's some of my mind-aids from antiquity:

a. Water. Sun (Energy) heats up the stuff from a body of water (Source), and it rises up (Hot side) into clouds.
The stuff condenses (dissipates or Works) in the clouds and now falls back (cold or Common side) and returns to body of water. We have a circle or circuit.

b. You sit on your office chair and push (Energy) into the air (Insulator - because the Energy does not have Effect on it..) You're not going anywhere...

Now move chair close to a wall, then sit.
You (Source of Energy) push against the wall with your muscles (Generator). The wall and floor are Conductors of this Energy up to the wheels. The wheels move (Energy dissipation or Work performed- Load).
The Energy flow or circle / circuit GOES from muscle (Energy) via walls/floor (Conductor) up to wheels. Energy is used up (Dissipated) by wheels moving (Work Load). Now Energy's RETURN path or completion of circuit is from the wheels on chair, back to the Source of Energy- You. The Resistance is the friction created in wheels running on the floor. The in-line "Switch" in this energy circuit is your arm....
The circle or circuit is complete.

c. Simple electrics;
Take a small flashlight. Remove battery (Energy Source) and the bulb (Load) out of it.
Run a cable (Conductor) between battery bottom and bulb metal side (or one of the bulb's wires). Touch (simulates Switch) the bottom of bulb (or other bulb wire) to battery top. Light is on /off Depending on "switch",
Light/Load circle/circuit is complete.

Here we have Battery (energy source) containing "muscle" or generator of energy, GOING from bottom of battery up to bulb (Load), then leaving load over other bulb side, RETURNING via Switch - (you intermittent touching) to battery (Source).
Circle / circuit is complete.
You can Alternate this scenario by reversing the battery in this circuit which makes the juice flow backwards, but it will still work the same, because the Energy or Voltage simply changes direction.

In all three cases, Energy only flows when Circuit is complete. The higher level of created Energy, be it muscle or EMF (Electro Motive Force - a ten dollar word for juice...) pushes back against a fixed ground.

Now let's look at Energy route for the juice needed by the 701.
In a simplified way, a large generator (Hydro dam or such) creates Energy at around 760,000 volts and has it GOING to your local transformer sub-station via high tension wires on towers. The RETURN is via earth, back to the Hydro dam / Generator.
This 760,000 volts will push against the zero potential of the earth.
That's the first circle/Circuit.
From the local sub-station , where it is transformed to a lower 3,000 volts or so, it GOES via the top wire (Conductor)on your telephone post to the transformer on your nearest post (or in front of house). That outside transformer also needs to complete its circuit with the local substation and it's done by connecting a RETURN wire into the ground. The earth is the COMMON conductor back to the sub station and the Hydro dam.
That's the second Circuit.
Next, we see a transformer on the telephone pole or at floor level, outside your house. It has the 220 volts GOING into your fuse panel. The heavy ground cable (Conductor) in the fuse panel RETURNS to the transformer again via ground or Earth.
That is a third Circuit.
The fuse panel sends the Hot or GOING Energy from either side of the panel juice, via in-line breakers (Switches) GOING in black conductor wires to the room outlet. The other RETURN or white wire, leads back to the same panel and as you pointed out, via Earth or ground, tying it to that big transformer on the pole (or wherever it sits..) and really to all the COMMON, zero potential earth / ground, including right back to the Hydro Generator.

Initially, we have nothing (no Load) across the AC Socket's GOING/Black wire and RETURNING white wire, therefore nothing happens, because air is a good insulator as we saw. This last Circuit is open.
Plug in the 701 and nothing happens still, if switch is open. One wire of the AC cord goes to the 701's transformer via pin 4 in 701 power box. That line has a fuse which acts as a one-shot-switch for safety. That line/Conductor can be called Common since it isn't switched.
The other wire of the AC cord, ends at pin 2. The 701's paddle switch, when flipped on, goes to pin 3. From pin 3 we go directly into the 110 voltage part of the transformer. Just ignore the 220 volts wire on the transformer...
So, to complete the 701 circuit, we have one side of the transformer on the AC outlet and the other side with a switch in line, on the other side of the outlet. Since we can flip the plug around, we don't care which wire is GOING or RETURNING. As long as the 701 flip switch is closed, power will flow as we saw with the reversal of the flashlight battery.
In order for the 701 to spin records, we see that in this exercise, we passed through three circles of power or Electrical circuits. Each circuit ran on a higher voltage and is transformed to a lower voltage at the end of each circuit, until we finally split the 220 to 110 in our house.
So much for circuits and electrical supply,
In your endeavor to place another switch into the 701, my first suggestion is
DON'T.
You will:
a. lower the value of the unit if you modify the turntable
b. be at serious risk of shock if the switch and wires are not handled properly.
c. the unit does not need to be on all the time for spin up.
The motor can be kept running if you do not allow the arm to fully return to the rest post. This can be done by blocking the return path over the rest post. There is no damage whatsoever to the slip clutches, if the arm is inhibited from making a full return to rest post. Just slip a pill bottle over the rest post....

Still not satisfactory? OK, for purely intellectual gain and with a warning to take care with wiring and open contacts, you can tap a spst switch such as simple (two screws) wall type light switch, run the two wires and tap them onto pins 2 and 3.
Your drawing already shows one side of your switch onto pin 2, so place the other one on pin 3.
I highly recommend you not to do this because you don't have a noise suppressor on that switch and if any wires are open, the danger from shock can be lethal.
Regards - with Safety Warnings,
k
Klaus Adlhoch, fmr. Assistant Service Manager,
Noresco -N.Q.I.-Dual of Canada,
Area of expertise: Tech Training and Consumer Service P.R.
Associated with Dual till Thompson era.
Favorite Duals: TG 12a, 1009, 721.
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby plexi » 19 Oct 2017 02:25

thanks, will ponder the 'going' chain of causation!....regarding the 701, as well designed as it is, if it is so different than most other turntables and needs the unique multi part, multi lubricated, perfect functioning entire apparatus to function and cannot be modded to turn on/off with a common switch,or more importantly be allowed to be setup to accomodate an aftermarket/separate arm, then that may be seen as a design flaw to some. Besides cosmetics,with my limited experience with them, that would be my only other critique of dual tables. The old garrards as well or any auto functioning table really, has to have many more moving parts to suit auto functions, than other tables, the AR xa being at the other end of the spectrum. The use of common parts and lower part count to my mind is a great design goal/achievement but it all hinges on manual operation. Frankly to my mind, the auto function idea generally, was a poor idea back in the 60's and doubt it will come back into vogue. I wonder if even 20-40k tables today are anything but manual tables,,most seem to be from what I can see. But my whole outlook is - DIY common parts simple design easily modifiable - based. If the world continues to devolve into anarchy, could one source a part to keep his turntable running so it will provide a respite from the storm, would be priority number one.

but regarding the last post, that has confused me more than anything. I now see the understanding of electricity with regard to stereos as a pure form of magic i will never comprehend. It may as well be running on purple unicorn juice as I understand that about as much. Why the 701 can't be safely modded to use a separate arm and turn on without death is a serious mystery. I now wonder am at risk of such a fate with my lencos, garrards, and AR as I've modified them to turn on/off with simple toggle switch, and all use separate aftermarket arms. All done with the non existent electrical knowledge I possess (also built a few 100W tube fender/hiwatt guitar amps that function amazingly!). All the tables have so far worked fine for years.. but they may be a simpler design as I've already suggested may be the case? Now turning on my stereo is tainted with the thought of seeing grandma earlier than expected instead of relaxing to music.

then forget the switch, although there are several 701 tables on the net where people seem to have forgone (removed) the stock switching and put in some simple on/off unless I'm not understanding what they did, but they are at risk of shock apparently....so if one where to have no switches (either stock or mod), is there no way to power up the 701 with everything bypassed (except needed safety cap .01uf cap?) so that when plugged in the unit safely powers up and when unplugged it safely stops. Imagine plugging the table into a basic outlet strip, where one can turn on his whole stereo at one time with it (meaning all components are left 'on' and global power is controlled at the outlet strip? I use a Lenco like this with success. This way the stock 701 wiring can be kept for the most part but still the mechanisms can be bypassed? also assume the disuse of stock arm so it will be left stationary. an arm on a separate armpod would be used...doable? safe? I'm guessing not but still wondering. regardless, will ponder the 'going' power chain outlined above and see if I can relate it to my real world experience....the creator made the sun and it all starts from that, so that is foundational and where all power seems to come from. How the creator got the power to make it is why he is the creator I suppose. the whole trillions of years came out of nothing, evolution nonsense is just that imo. and the flat earth has raised some serious questions that have no apparent answers. Why there is no pic/or better yet vid, of people haningoff the globe by their shoes or ocean liners and airplanes riding sideways and upside down is a serious gap in proof of concept/theory and relies on way to much faith/trust, especially when asked to trust known liars. but i digress
Garard 401 stanton881s rega rb303, Thorens125/Acos Lustre grado G, AR XA rega 200 ShureV15III MR, Lenco l70 rega rb202 Stanton881s, LCR loungeMM preamp
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Re: 701 Mod to standard toggle power switch .01 uf cap

Postby Tinkaroo » 20 Oct 2017 11:03

plexi wrote:thanks, will ponder the 'going' chain of causation!....regarding the 701, as well designed as it is, if it is so different than most other turntables and needs the unique multi part, multi lubricated, perfect functioning entire apparatus to function and cannot be modded to turn on/off with a common switch,or more importantly be allowed to be setup to accomodate an aftermarket/separate arm, then that may be seen as a design flaw to some.


Duals were designed to be a complete turntable and fully automatic, except for the semi-auto models. They were designed that way for the convenience of the end user. They were never intended to be modified by end users, and electrical modifications are potentially dangerous and deadly, so no manufacturer would condone them.

This is not a design flaw. Duals are actually well engineered and designed for their intended purpose and really require no modifications to perform as intended. Maintenance is required on anything that has ever been manufactured by anyone, especially after 40 years. The fact they have lasted so long says a lot about the quality.
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