Sander's Speed Controller

[Pete_fi]

Hi,

sorry to hear there was a fuse blow but this shouldn't be a big problem! Should you add a NTC (thermistor) or just use bigger fuses. I had similar issue with inrush current when powering on one of my amp and NTC fixed the problem. I couldn't use bigger/slower fuses on that circuit.

Best regards,
Pete

[john]

Malcolm,

Please add me to the list

John  2  UK

Thanks

[ropie]

Thankfully, that isn't what happened. Colin returned the controller to me and in fact all that had happened, was that the fuses on the supply transformer secondary had blown. I fitted new fuses and it is now working perfectly again.

Aye, you can't rely on Colin to replace a fuse   A big thanks to Nigel for loaning the controller out - it was a pleasure to test.  Let us know what the next step is as I'm itching to build my own now..

[gthang]

Aye, you can't rely on Colin to replace a fuse  A big thanks to Nigel for loaning the controller out - it was a pleasure to test.  Let us know what the next step is as I'm itching to build my own now..

I must admit, having seen and albeit briefly used Nigel's controller at your's the other week / month, I'm rather keen as well. Good news this is only a minor set back.

[LencoSpace]

Meanwhile, there is ONE final detail that I need to resolve, before I can start taking PCB orders and I will need some input from all of you. No time to write about it now, though. I'll get back to you ....

This sounds very good to me...Hope the moment we all are waiting for is near...)

[nigel]

Aye, you can't rely on Colin to replace a fuse  

Nah - I asked Colin to return it, because I was expecting far worse. Fuses don't usually blow for no reason (although thankfully, in this case, the reason was just lack of thought on my part!) 

sorry to hear there was a fuse blow but this shouldn't be a big problem! Should you add a NTC (thermistor) or just use bigger fuses. I had similar issue with inrush current when powering on one of my amp and NTC fixed the problem. I couldn't use bigger/slower fuses on that circuit.

Hi Pete,

NTC's would be fine on the mains (primary) side of the transformer, but in this case it's the fuses on the secondary side which blew. I'm a bit reluctant to go down the NTC route on the secondary side, as the current there is quite high and continuous, so they would need to be quite big & would get quite hot (and be quite expensive). It's worth considering one on the output transformer, though, maybe  I'll think about that ...

[Pete_fi]

^OK! Just my 2cent how I fixed another blowing fuse issue Just change to bigger fuses and order the boards 

[GP49]

^OK! Just my 2cent how I fixed another blowing fuse issue Just change to bigger fuses and order the boards 

Why bother?  Just wrap the blown fuse in aluminium foil.   

[tomatamot]

Just wrap the blown fuse in aluminium foil.   

 

[Pete_fi]

I didn't say it, didn't I      

[willbewill]

Why bother?  Just wrap the blown fuse in aluminium foil.   

I find 6 inch nails good

[john]

I find 6 inch nails good

But the audio grade 6 nines silver plated nails are the Best 

[colin]

Mmmm, emergency fuse alternatives ............ yes I have all of those, although I prefer the cryo'd gold plated 6" nails for best sound!     I figured when the controller melted those it was best to send it back to Nigel quick quick!!   

What's it like using the controller?  Simply put - it leaps the Lenco design from the 1950s straight into the 21st Century, and then some!

Let's look at Nigel's creation, first the controls -

On the left is a 3 position rotary switch for 3 speeds - the next 3 controls are the speed adjusters and an led above each one lights when that speed is selected.   I think the Lenco mechanical speed change is the best of it's type among the comtemporary idler competition, but using this controller is seductive, you don't want to like it (all that electronics!!) but you can't help it.     Switching speeds produces near instant reaction - no need to feel envious of slick high quality DD decks with their push button speed change and pitch adjusters - and this one has individual pitch adjusters for each speed.   These operations all happen with commendable smoothness - which inspires confidence and makes it difficult to imagine how to improve it.  Let's move on -

Next right is a Voltmeter and far right is the voltage adjuster.  Imo best at 220v for that relentless Lenco leading edge management. Want to enjoy a more laid back TD150 type of sound?  Just knock back the voltage to 150v or so. 

A universal turntable controller with all the bells and whistles you could wish for.  Can you understand how gutted I was when it went wrong? 

Thanks for fixing it under warranty Nigel, can I have it back now please?   

 

PS  Does it change the sound?  Using my system with UK domestic mains power, I did not notice any repeatable difference in the sound with or without the controller. Of course my experiments were cut short so there's lot's more testing to be done. 

It would be interesting to try the controller at Scalford Hall later this year to see if we can repeat the improvement over (noisy?) raw mains that many heard there when using a similar controller three years ago. 

[rfgumby]

NTC's would be fine on the mains (primary) side of the transformer, but in this case it's the fuses on the secondary side which blew. I'm a bit reluctant to go down the NTC route on the secondary side, as the current there is quite high and continuous, so they would need to be quite big & would get quite hot (and be quite expensive). It's worth considering one on the output transformer, though, maybe  I'll think about that ...

I've got some thermistors if you'd like to try them on the primaries.  Let me know if you need me to send some over.  I bought a bunch when I built some OTL amps, I have maybe 10 laying around.

[nigel]

Mmmm, emergency fuse alternatives ............ yes I have all of those, although I prefer the cryo'd gold plated 6" nails for best sound!     I figured when the controller melted those it was best to send it back to Nigel quick quick!!   

What's it like using the controller?  Simply put - it leaps the Lenco design from the 1950s straight into the 21st Century, and then some!

Let's look at Nigel's creation, first the controls -

On the left is a 3 position rotary switch for 3 speeds - the next 3 controls are the speed adjusters and an led above each one lights when that speed is selected.   I think the Lenco mechanical speed change is the best of it's type among the comtemporary idler competition, but using this controller is seductive, you don't want to like it (all that electronics!!) but you can't help it.     Switching speeds produces near instant reaction - no need to feel envious of slick high quality DD decks with their push button speed change and pitch adjusters - and this one has individual pitch adjusters for each speed.   These operations all happen with commendable smoothness - which inspires confidence and makes it difficult to imagine how to improve it.  Let's move on -

Next right is a Voltmeter and far right is the voltage adjuster.  Imo best at 220v for that relentless Lenco leading edge management. Want to enjoy a more laid back TD150 type of sound?  Just knock back the voltage to 150v or so. 

A universal turntable controller with all the bells and whistles you could wish for.  Can you understand how gutted I was when it went wrong? 

Thanks for fixing it under warranty Nigel, can I have it back now please?   

 

PS  Does it change the sound?  Using my system with UK domestic mains power, I did not notice any repeatable difference in the sound with or without the controller. Of course my experiments were cut short so there's lot's more testing to be done. 

It would be interesting to try the controller at Scalford Hall later this year to see if we can repeat the improvement over (noisy?) raw mains that many heard there when using a similar controller three years ago. 

Colin,

many thanks for your comments and sorry the unit went t*ts-up on you, but at least it helped to highlight an (easily fixable!) problem. 

No, you can't have it back 

Oh ... well alright then, but I have a bit of fiddling to do first, so I'll get it back to you "in due course", certainly before Scalford.