I have been around long enough to remember people using prop pitch motors as rotators. I actually feel quite lucky to have known so many people licensed before WW2 and getting to visit their shacks.
Thanks for this video! I had already purchased a Yaesu 450 for a hex beam based on the wind load rating of the rotator and the wind load of the antenna but still found the video interesting. Recently I helped install a hex beam on a big tower which provided great insight for my own project. Torque is not materially affected by the length of the tube between the rotator and the antenna as there is just not enough force applied on the system to reach the torque limits of the connecting tube. It is much better IMO to have a tube and thrust bearing than to mount the antenna directly to the rotator. The thrust bearing can carry all of the weight. It adds cost but it really helps the rotator do its job and it reduces wear. The ability of the rotator to start and stop the antenna (torque rating) and to maintain its position and tolerate wind loads are the most important factors.
Correct, torque is no affected by length, but there is a significant magnification of transmitted force that is put on the rotator. Long screwdriver effect.
Hi Peter, interesting presentation, thank you. I have been using the now obsolete Emotator 1200X for almost 40 years and did a complete rebuild 3 years ago. I agree with all you say and the best rotator is the one or two models from the range above that of the design minimum recommended for your proposed aerial array. It will be worth the extra spend in the long run and as you so rightly say, no getting cold and wet during a winter breakdown. Fortunately there is much information online concerning old rotators and spare parts are available if you search. 73, Martin GW3XJQ
Again a great video Peter, thanks for that. I'm just using a folded X-beam wire antenna for 6 bands (20-6) Little windload and only 8 kg in total. I played on safe and mounted a G-1000DXC rotor under it. Should last forever. 73 de OO4M
Two dead rotators here, Daiwa DC 7011 Kenpro KR-400RC Turned out that the Kenpro uses exactly the same head unit as the Diawa. The problem is basically a poor if not incompetent design. There are NO end stop switches in the system, when the antenna hits the stops the motor keeps going and relies on a slipping clutch to save it. That does not work well and the motor burns out. These are 24V ac two phase motors you switch the phases to change direction. The advantage is that there is no electrical noise. The disadvantage is that spares are almost impossible to get now. (these are old rotators ) I have a long term project on the bench to rebuild them into something rather more robust, but as will all my projects other things get in the way 🙂 I see that the newer rotators now use a dc motor with limit switches that cut the power. So a much better design. The simplest roatator I ever had was for my 6 ele 144Mhz quad it was a couple of lengths of orange nylon garden cord tied to the ends. The strings came into the shack (bedroom) via the fanlight window So 180 degree rotation was easy. With a little practice I could let the antenna spin until the strings crossed and then the other 180 direction could be "beamed up" That worked really well for many years... Andy
I had a Channelmaster with thrustbearing to turn 5-el 6m, 9-el 2m, 19-el 70cm and an X-200 on top. Survived a gale 10 and worked well for over 10 years, with a little annual TLC. I figured I could thrash 3 of these for the price of one Yaesu, but I never did.
Hi Peter, my first rotator was a Stolle TV antenna rotator, I used it with 2 bearings, worked fine. 2m, 70cm, 23cm Yagis. When I wanted to install a 2m Dish ,plus Yagis, I changed to a Kenpro KR600 plus bearing. It worked for more than 35 years until a hurricane. Then he needed a Dentist. 2 teeth broken. Kenpro didn't exist anymore,so no new couronne. I scrapped it.😮
Comments can be tongue in cheek, think twice about the expense, especially if a elevated vertical works just as well as a beam anyway. I did try a rotator on my vertical, but didn't get any gain. Hi. 73 mate.
No idea why the RUclips word police is highlighting "ma5b" in blue ... But when you click on the "computer knows best" link, it takes you to some weird images of console game toy weapon... 🧐 Lucky you didn't type the words COVID , vaccine , climate , or marzipan ... God only knows what links they would have taken us to ... 😂
Hi Peter, not wishing to be rude but your screwdriver idea doesn't realy hold. Its the thickness of the handle that increases the torque. To give you an example of torque, it's force times distance or in old money, pounds per foot. Try pushing your front door open an inch from the hinges, then do so from the opposite end to the hinge, you will feel the difference of torque. Sorry if I am teaching anyone to suck eggs here, but thought it may help someone get the concept.
I once had a auto rotator in my parents loft turning a 2 metre yagi. One day it jammed on the end stop, overloading the motor and getting very hot! Is was by chance that I went to the loft and smelt the heat. The rotor body stayed hot for a considerable time. Be warned! G4BTI.
I have been around long enough to remember people using prop pitch motors as rotators. I actually feel quite lucky to have known so many people licensed before WW2 and getting to visit their shacks.
Ah yes I remember prop pitch motors
Thanks for this video! I had already purchased a Yaesu 450 for a hex beam based on the wind load rating of the rotator and the wind load of the antenna but still found the video interesting. Recently I helped install a hex beam on a big tower which provided great insight for my own project. Torque is not materially affected by the length of the tube between the rotator and the antenna as there is just not enough force applied on the system to reach the torque limits of the connecting tube. It is much better IMO to have a tube and thrust bearing than to mount the antenna directly to the rotator. The thrust bearing can carry all of the weight. It adds cost but it really helps the rotator do its job and it reduces wear. The ability of the rotator to start and stop the antenna (torque rating) and to maintain its position and tolerate wind loads are the most important factors.
Correct, torque is no affected by length, but there is a significant magnification of transmitted force that is put on the rotator. Long screwdriver effect.
Hi Peter, interesting presentation, thank you.
I have been using the now obsolete Emotator 1200X for almost 40 years and did a complete rebuild 3 years ago. I agree with all you say and the best rotator is the one or two models from the range above that of the design minimum recommended for your proposed aerial array. It will be worth the extra spend in the long run and as you so rightly say, no getting cold and wet during a winter breakdown.
Fortunately there is much information online concerning old rotators and spare parts are available if you search.
73,
Martin GW3XJQ
Thanks for sharing Martin.
Again a great video Peter, thanks for that. I'm just using a folded X-beam wire antenna for 6 bands (20-6) Little windload and only 8 kg in total. I played on safe and mounted a G-1000DXC rotor under it. Should last forever. 73 de OO4M
Sounds great!
Two dead rotators here,
Daiwa DC 7011 Kenpro KR-400RC
Turned out that the Kenpro uses exactly the same head unit as the Diawa.
The problem is basically a poor if not incompetent design. There are NO end stop switches in the system, when the antenna hits the stops the motor keeps going and relies on a slipping clutch to save it. That does not work well and the motor burns out.
These are 24V ac two phase motors you switch the phases to change direction. The advantage is that there is no electrical noise. The disadvantage is that spares are almost impossible to get now. (these are old rotators )
I have a long term project on the bench to rebuild them into something rather more robust, but as will all my projects other things get in the way 🙂
I see that the newer rotators now use a dc motor with limit switches that cut the power. So a much better design.
The simplest roatator I ever had was for my 6 ele 144Mhz quad it was a couple of lengths of orange nylon garden cord tied to the ends. The strings came into the shack (bedroom) via the fanlight window So 180 degree rotation was easy. With a little practice I could let the antenna spin until the strings crossed and then the other 180 direction could be "beamed up"
That worked really well for many years...
Andy
I had a Channelmaster with thrustbearing to turn 5-el 6m, 9-el 2m, 19-el 70cm and an X-200 on top. Survived a gale 10 and worked well for over 10 years, with a little annual TLC. I figured I could thrash 3 of these for the price of one Yaesu, but I never did.
Great video, thank you! I'm very tempted to use a rotator... in my loft, to use with a magnetic loop! 😂
Peter , have you been watching callum 's channel DX COMMANDER by any chance???
Why, what happened
Hi Peter, my first rotator was a Stolle TV antenna rotator, I used it with 2 bearings, worked fine. 2m, 70cm, 23cm Yagis. When I wanted to install a 2m Dish ,plus Yagis, I changed to a Kenpro KR600 plus bearing. It worked for more than 35 years until a hurricane. Then he needed a Dentist. 2 teeth broken. Kenpro didn't exist anymore,so no new couronne. I scrapped it.😮
Gosh, names from the past that I had forgotten!
Comments can be tongue in cheek, think twice about the expense, especially if a elevated vertical works just as well as a beam anyway. I did try a rotator on my vertical, but didn't get any gain. Hi. 73 mate.
Thanks for this Peter. Any thoughts on where on a pole you should place the rotator🤔
At the top.
At least you call them by the proper name a 'Rotator' in the UK. 🙂
Nice to hear!
G650 here with a ma5b and previously a hex beam no issues 10 years.
No idea why the RUclips word police is highlighting "ma5b" in blue ... But when you click on the "computer knows best" link, it takes you to some weird images of console game toy weapon... 🧐
Lucky you didn't type the words COVID , vaccine , climate , or marzipan ... God only knows what links they would have taken us to ... 😂
Thanks, Peter. thats a handy video 73
Hmmm sounds like a dig at Mr Commander
Why, what happened.
good video and nice info. can you make a video about different loop antennas it would be nice 🙂 La2vla
Hi Peter, not wishing to be rude but your screwdriver idea doesn't realy hold. Its the thickness of the handle that increases the torque.
To give you an example of torque, it's force times distance or in old money, pounds per foot. Try pushing your front door open an inch from the hinges, then do so from the opposite end to the hinge, you will feel the difference of torque.
Sorry if I am teaching anyone to suck eggs here, but thought it may help someone get the concept.
Yes torque is easy to demonstrate. But there is an additional transmitted force. That is why we normally place the rotator at the top of the mast.
I once had a auto rotator in my parents loft turning a 2 metre yagi. One day it jammed on the end stop, overloading the motor and getting very hot!
Is was by chance that I went to the loft and smelt the heat. The rotor body stayed hot for a considerable time. Be warned!
G4BTI.
Good job there was no fire in the loft!