Rotator problem


g4zod@btinternet.com
 

I have acquired a second hand Daiwa 7500 A rotator. ( The one on my mast is dying after nearly 30+ years of use)
The replacement rotator seems to have an intermittent rotary potentiometer in the head unit. It seems to be a 360 degree device. (500K?) I did a search on the web but it seems they may be " specials" and not available.
Can anybody  advise me to where   could  a replacement.
It would be a shame to dump this rotator which is much better than my existing one.
Many thanks.
Julian
G4ZOD

Sent from BlueMail


Gordon GI6ATZ
 

Hi Julian

Its more likely to be a 500 ohm pot and they’re a bit like hens teeth to obtain!
A quick Google did find a supplier but the price was a bit much - €39.99!

Gordon
GI6ATZ


Andy G4JNT
 

If anyone has worked out a way, for someone with no mechanical engineering skills, to insert an optical or Hall effect sensor then let me know.    I've been pondering ways to get rid of that awful 500Ω  two-terminal pot for ages.    But all ideas need a machining solution.
Why couldn't they have made it a three terminal potential divider.   Removes much of the troubles with dirt



On Fri, 11 Jun 2021 at 17:02, Gordon GI6ATZ via groups.io <gordon.curry=btinternet.com@groups.io> wrote:

Hi Julian

Its more likely to be a 500 ohm pot and they’re a bit like hens teeth to obtain!
A quick Google did find a supplier but the price was a bit much - €39.99!

Gordon
GI6ATZ


g4zod@btinternet.com
 

I have now taken out the potentiometer and it would appear to be 500 Ohms as has been pointed out.
The pot. has three wire connections. The reading from it are erratic!
I do have full mechanical facilities and would like to find an alternative way of repairing the rotator.
Julian

Sent from BlueMail

On 11 Jun 2021, at 17:08, Andy G4JNT <andy.g4jnt@...> wrote:
If anyone has worked out a way, for someone with no mechanical engineering skills, to insert an optical or Hall effect sensor then let me know.    I've been pondering ways to get rid of that awful 500Ω  two-terminal pot for ages.    But all ideas need a machining solution.
Why couldn't they have made it a three terminal potential divider.   Removes much of the troubles with dirt



On Fri, 11 Jun 2021 at 17:02, Gordon GI6ATZ via groups.io <gordon.curry= btinternet.com@groups.io> wrote:

Hi Julian

Its more likely to be a 500 ohm pot and they’re a bit like hens teeth to obtain!
A quick Google did find a supplier but the price was a bit much - €39.99!

Gordon
GI6ATZ


ian hope (2E0IJH)
 

Sent you a PM
 
Ian
M5IJH

 
 
Sent: Friday, June 11, 2021 at 5:21 PM
From: "g4zod@... via groups.io" <g4zod@...>
To: ukmicrowaves@groups.io
Subject: Re: [UKMicrowaves] Rotator problem
I have now taken out the potentiometer and it would appear to be 500 Ohms as has been pointed out.
The pot. has three wire connections. The reading from it are erratic!
I do have full mechanical facilities and would like to find an alternative way of repairing the rotator.
Julian
 
Sent from BlueMail
On 11 Jun 2021, at 17:08, Andy G4JNT <andy.g4jnt@...> wrote:
If anyone has worked out a way, for someone with no mechanical engineering skills, to insert an optical or Hall effect sensor then let me know.    I've been pondering ways to get rid of that awful 500Ω  two-terminal pot for ages.    But all ideas need a machining solution.
Why couldn't they have made it a three terminal potential divider.   Removes much of the troubles with dirt
 
Andy
 
 
On Fri, 11 Jun 2021 at 17:02, Gordon GI6ATZ via groups.io <gordon.curry= btinternet.com@groups.io> wrote:

Hi Julian

Its more likely to be a 500 ohm pot and they’re a bit like hens teeth to obtain!
A quick Google did find a supplier but the price was a bit much - €39.99!

Gordon
GI6ATZ

 

 


Andy G4JNT
 

Yes, it could be wired as three terminal.  But I never found a way to isolate the wiper from chassis, which makes feedback difficult



On Fri, 11 Jun 2021 at 17:21, g4zod@... via groups.io <g4zod=btinternet.com@groups.io> wrote:
I have now taken out the potentiometer and it would appear to be 500 Ohms as has been pointed out.
The pot. has three wire connections. The reading from it are erratic!
I do have full mechanical facilities and would like to find an alternative way of repairing the rotator.
Julian

Sent from BlueMail
On 11 Jun 2021, at 17:08, Andy G4JNT <andy.g4jnt@...> wrote:
If anyone has worked out a way, for someone with no mechanical engineering skills, to insert an optical or Hall effect sensor then let me know.    I've been pondering ways to get rid of that awful 500Ω  two-terminal pot for ages.    But all ideas need a machining solution.
Why couldn't they have made it a three terminal potential divider.   Removes much of the troubles with dirt



On Fri, 11 Jun 2021 at 17:02, Gordon GI6ATZ via groups.io <gordon.curry= btinternet.com@groups.io> wrote:

Hi Julian

Its more likely to be a 500 ohm pot and they’re a bit like hens teeth to obtain!
A quick Google did find a supplier but the price was a bit much - €39.99!

Gordon
GI6ATZ


Dave (G1OGY)
 

On Fri, 11 Jun 2021 at 15:23, g4zod@btinternet.com via groups.io
<g4zod=btinternet.com@groups.io> wrote:

Can anybody advise me to where could a replacement.
You could try Yaesu UK "Spares Dept"

Dave, G1OGY


R Hopkins
 

Hi Julian

It's 500 Ohm pot.

It may not be a 360 degree pot because it may be geared so that it only does around 270 degrees for
a full rotation of the rotator. I had mine in bits last summer but I can't remember if that was the
case. So don't take that as gospel.

I've got a copy of the owners manual (the one that was supplied with it from new). You can find it
on the 'net.

Roger GW4NOS

On Fri, 11 Jun 2021 15:23:30 +0100, you wrote:

I have acquired a second hand Daiwa 7500 A rotator. ( The one on my mast is dying after nearly 30+ years of use)
The replacement rotator seems to have an intermittent rotary potentiometer in the head unit. It seems to be a 360 degree device. (500K?) I did a search on the web but it seems they may be " specials" and not available.
Can anybody  advise me to where   could  a replacement.
It would be a shame to dump this rotator which is much better than my existing one.
Many thanks.
Julian
G4ZOD

?Sent from BlueMail ?




ian hope (2E0IJH)
 

The Only people That had any were BKW in germany or Peter Duro In australia last time I wanted some and I bought all of Peters 2nd Hand stock to keep our contest units going.
 
You Can fit a RA25Y20s if you can find one, but these have stops and you have to get allingment correct as the original was a 360 deg, where as a RA25y isnt
 
 
Ian
M5IJH

 
 
Sent: Friday, June 11, 2021 at 5:35 PM
From: "Dave (G1OGY)" <g1ogy@...>
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Rotator problem
On Fri, 11 Jun 2021 at 15:23, g4zod@... via groups.io
<g4zod@...> wrote:
>
> Can anybody advise me to where could a replacement.

You could try Yaesu UK "Spares Dept"

Dave, G1OGY




 


Gordon GI6ATZ
 

https://stecker-shop.net/epages/27edac8b-bca1-4619-a0d8-f53e62f2ef2c.sf/de_DE/?ViewObjectPath=%2FShops%2F27edac8b-bca1-4619-a0d8-f53e62f2ef2c%2FProducts%2F01951


Colin Ranson
 

I have an AR40 that uses a 500ohm (I think) feedback pot. I have tried as an experiment, several circuits to feed a NSN meter (ex EMOTATOR) but with no luck.... I really need three terminals from the pot but one end is either not connected or grounded. Its only a whim to watch a needle, the existing controller (set direction and push down) is ok.

 

I’m wondering if a KR400 controller is compatible ?

 

Any suggestions welcomed.

 

Regards

 

Colin de G8LBS.

 

Sent from Mail for Windows 10

 

From: R Hopkins via groups.io
Sent: 11 June 2021 17:39
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Rotator problem

 

Hi Julian

It's 500 Ohm pot.

It may not be a 360 degree pot because it may be geared so that it only does around 270 degrees for
a full rotation of the rotator. I had mine in bits last summer but I can't remember if that was the
case. So don't take that as gospel.

I've got a copy of the owners manual (the one that was supplied with it from new). You can find it
on the 'net.

Roger    GW4NOS

On Fri, 11 Jun 2021 15:23:30 +0100, you wrote:

>I have acquired a second hand Daiwa 7500 A rotator. ( The one on my mast is dying after nearly 30+ years of use)
>The replacement rotator seems to have an intermittent rotary potentiometer in the head unit. It seems to be a 360 degree device. (500K?) I did a search on the web but it seems they may be " specials" and not available.
>Can anybody  advise me to where   could  a replacement.
>It would be a shame to dump this rotator which is much better than my existing one.
>Many thanks.
>Julian
>G4ZOD
>
>?Sent from BlueMail ?
>
>
>
>






 


ian hope (2E0IJH)
 

Ar40 is 1K but the circuit is the same as G400 RC, but that use's 500ohms, I would imagine you could change the ar40 to 500 ohms, it only uses 2 wires from pot, centre and one end, G400RC is the same
 
Ian
M5IJH
 
Sent: Friday, June 11, 2021 at 6:11 PM
From: "Colin Ranson" <g8lbs@...>
To: "UKMicrowaves@groups.io" <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] Rotator problem

I have an AR40 that uses a 500ohm (I think) feedback pot. I have tried as an experiment, several circuits to feed a NSN meter (ex EMOTATOR) but with no luck.... I really need three terminals from the pot but one end is either not connected or grounded. Its only a whim to watch a needle, the existing controller (set direction and push down) is ok.

 

I’m wondering if a KR400 controller is compatible ?

 

Any suggestions welcomed.

 

Regards

 

Colin de G8LBS.

 

Sent from Mail for Windows 10

 

From: R Hopkins via groups.io
Sent: 11 June 2021 17:39
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Rotator problem

 

Hi Julian

It's 500 Ohm pot.

It may not be a 360 degree pot because it may be geared so that it only does around 270 degrees for
a full rotation of the rotator. I had mine in bits last summer but I can't remember if that was the
case. So don't take that as gospel.

I've got a copy of the owners manual (the one that was supplied with it from new). You can find it
on the 'net.

Roger    GW4NOS

On Fri, 11 Jun 2021 15:23:30 +0100, you wrote:

>I have acquired a second hand Daiwa 7500 A rotator. ( The one on my mast is dying after nearly 30+ years of use)
>The replacement rotator seems to have an intermittent rotary potentiometer in the head unit. It seems to be a 360 degree device. (500K?) I did a search on the web but it seems they may be " specials" and not available.
>Can anybody  advise me to where   could  a replacement.
>It would be a shame to dump this rotator which is much better than my existing one.
>Many thanks.
>Julian
>G4ZOD
>
>?Sent from BlueMail ?
>
>
>
>





 

 


Colin Ranson
 

Thanks Ian that’s been helpful

 

Regards

 

Colin de G8LBS.

 

Sent from Mail for Windows 10

 

From: ian hope (2E0IJH)
Sent: 11 June 2021 18:17
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Rotator problem

 

Ar40 is 1K but the circuit is the same as G400 RC, but that use's 500ohms, I would imagine you could change the ar40 to 500 ohms, it only uses 2 wires from pot, centre and one end, G400RC is the same

 

Ian

M5IJH

 

Sent: Friday, June 11, 2021 at 6:11 PM
From: "Colin Ranson" <g8lbs@...>
To: "UKMicrowaves@groups.io" <UKMicrowaves@groups.io>
Subject: Re: [UKMicrowaves] Rotator problem

I have an AR40 that uses a 500ohm (I think) feedback pot. I have tried as an experiment, several circuits to feed a NSN meter (ex EMOTATOR) but with no luck.... I really need three terminals from the pot but one end is either not connected or grounded. Its only a whim to watch a needle, the existing controller (set direction and push down) is ok.

 

I’m wondering if a KR400 controller is compatible ?

 

Any suggestions welcomed.

 

Regards

 

Colin de G8LBS.

 

Sent from Mail for Windows 10

 

From: R Hopkins via groups.io
Sent: 11 June 2021 17:39
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Rotator problem

 

Hi Julian

It's 500 Ohm pot.

It may not be a 360 degree pot because it may be geared so that it only does around 270 degrees for
a full rotation of the rotator. I had mine in bits last summer but I can't remember if that was the
case. So don't take that as gospel.

I've got a copy of the owners manual (the one that was supplied with it from new). You can find it
on the 'net.

Roger    GW4NOS

On Fri, 11 Jun 2021 15:23:30 +0100, you wrote:

>I have acquired a second hand Daiwa 7500 A rotator. ( The one on my mast is dying after nearly 30+ years of use)
>The replacement rotator seems to have an intermittent rotary potentiometer in the head unit. It seems to be a 360 degree device. (500K?) I did a search on the web but it seems they may be " specials" and not available.
>Can anybody  advise me to where   could  a replacement.
>It would be a shame to dump this rotator which is much better than my existing one.
>Many thanks.
>Julian
>G4ZOD
>
>?Sent from BlueMail ?
>
>
>
>





 

 

 


Nick Peckett G4KUX
 

Try Duoro Services in VK land, he specalises in Rotator refurbisment and knows a lot about the Daiwa product, he may well have a spare pot. www.kur02.com.au He supplied me with some spares for a Diawa Multitorque roror I was refubishing. Not the cheapest but quite helpful.

Regards

Nick G4KUX

On 11/06/2021 15:23, g4zod@... via groups.io wrote:
I have acquired a second hand Daiwa 7500 A rotator. ( The one on my mast is dying after nearly 30+ years of use)
The replacement rotator seems to have an intermittent rotary potentiometer in the head unit. It seems to be a 360 degree device. (500K?) I did a search on the web but it seems they may be " specials" and not available.
Can anybody  advise me to where   could  a replacement.
It would be a shame to dump this rotator which is much better than my existing one.
Many thanks.
Julian
G4ZOD

Sent from BlueMail


ian hope (2E0IJH)
 

Peter's about the only person that has bits for G400/G600's the diawa 7500 uses the same casing, so likely very similar inside
 
Ian
M5IJH

 
 
Sent: Friday, June 11, 2021 at 7:58 PM
From: "Nick Peckett G4KUX" <nick@...>
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] Rotator problem

Try Duoro Services in VK land, he specalises in Rotator refurbisment and knows a lot about the Daiwa product, he may well have a spare pot. www.kur02.com.au He supplied me with some spares for a Diawa Multitorque roror I was refubishing. Not the cheapest but quite helpful.

Regards

Nick G4KUX

On 11/06/2021 15:23, g4zod@... via groups.io wrote:
I have acquired a second hand Daiwa 7500 A rotator. ( The one on my mast is dying after nearly 30+ years of use)
The replacement rotator seems to have an intermittent rotary potentiometer in the head unit. It seems to be a 360 degree device. (500K?) I did a search on the web but it seems they may be " specials" and not available.
Can anybody  advise me to where   could  a replacement.
It would be a shame to dump this rotator which is much better than my existing one.
Many thanks.
Julian
G4ZOD
 
Sent from BlueMail


F1CHF
 

I see this article (use a 10 turns 5 k potentiometer)
500 ohms 360 degres seems hard to find ..
 
see here
 
 
francois F1CHF