Calebson

I don't have a lot of knowledge in this area, so I'm looking for some advice. I was looking for a tx/rx to use for basic robotic controls. I have a guy that has some for sale and is asking for my offer, but I don' want to offend him with an inappropriate number. He has a Futaba FP-T7UHP super, pcm 1024, and a Futaba FP- T6NFK conquest along with a couple of rx. What is a respectable offer for me to make him for these ?

flyinwalenda

My Feedback: (5)

If they work and look OK, I'd say $35.00 for the Super , $15.00 for the Conquest and $5.00 each for the receivers.

rgburrill

Hold the phone there cowboy. In all likelihood those are 72 MHz radios and their use in anything other than an airborne system is illegal. For that robot you must use 75 MHz not 72 MHz. You don't want to be shooting down anyone's expensive aircraft now do you? You should just stick with 2.4GHz to be safe. HobbyKing has a very inexpensive system call the Turnigy i6S and it comes with an iBus receiver so you can spread out those servos.

rgburrill

BTW, if you want something cheaper I have a 4 channel Conquest on 75MHz with a receiver and servo that I used on a boat for $25 plus shipping. I'm actually in Oklahoma, not Connecticut.

JohnBuckner

My Feedback: (1)

Working or not the Conquest is worthless. First perhaps you need to understand about frequency bands and not sure you do. First the standard these days and has been for a lot of years now is 2.4 however neither of those two are, the Conquest is AM or possibly FM, They were produced both ways and if it is AM there is a possibility it is wideband which makes it illegal for use in the US.

Also and this applies to both units, what frequency band are they on? If they are old air units (intended for RC airplanes) they are on 72MHz but if they were used for surface operations (cars, boats, tanks, robotics) those old FM units by FCC regulation must be on the 75MHz band.

No in my opinion neither of those units have any value at all and there are many other pitfalls waiting for you that is going be expensive indeed.

John

Calebson

what is the range on these? I didn't realize it could be illegal. I just need something that will go 50 feet max. I use it to control a couple of servos connected to switches, which control 2 motors on 2 wheels as a "drivetrain"

Calebson

so what would you recommend I use ? You are right, I am very inexperienced which is why i came here for some advice. Im just trying to control a couple of servos to run a couple of motors for use as wheels

rgburrill

With all due respect John you have no idea who I am or what I know about RC. While 2.4 GHz has become the standard there are many, many 72 and 75 MHz radios still in use today.. There is nothing wrong with them as long as they are narrowband units. They are certainly NOT worthless except to those who are 2.4GHz bigots.

I have never seen 6 or 7 band 75 MHz units. Not saying they weren't built but I have never seen one. Mine is a 4 channel FM, narrowband unit on 75 MHz and is perfectly legal to use for surface use.

rgburrill

72 and 75 MHz FM radios have a line-of-sight range of over 3 miles. The better 2.4GHz units are typically limited to 3500 feet but the cheaper ones have trouble getting past 1000, especially on the ground. But for 50 feet you should not have a problem with most.

init4fun

RG , If I had to guess , I'd guess John's statement was intended for Calebson and not you . Calebson has himself stated he knows nothing of RC and that's why he's here .

PS , To Calebson , while 75 MHZ systems would indeed work fine for your robot , one possible advantage of 2.4 GHZ is the far shorter antenna required for both the transmitter and receiver . A TX antenna for 75 MHZ is right around 3 ish feet long whereas a 2.4 TX antenna is usually no longer than 6 inches , with some newer 2.4 GHZ setups having no visable antenna protruding from the TX at all .

JohnBuckner

My Feedback: (1)

My single post in this thread was in direct response to the Calebson and him only in an attempt to help prevent him squandering his money down a potentially very rocky road.

My opinion stands! If one must apply a monetary value to those two, (the OP's listed two) the Conquest is worthless and the other not worth much more.

John

Truckracer

My Feedback: (19)

Sadly, I have to agree regarding the worth of these radios. Unless a particular radio has collector value or it is a high end radio, 72 - 75 MHz equipment has very little value these days. I wish it was otherwise but the market dictates this. I have a cupboard full of older radios that I just keep around for the memories and occasionally give something away when someone is trying to keep an old system going.

init4fun

Well said to both truckracer and John , the greatest majority of the old RC stuff (72/75 MHZ) while still functional is just about worthless . While some may place some sentimentality to the older equipment the fact is that to the majority of RC hobbyists the old equipment holds about as much value as the old TV remote control for the TV that got thrown out 10 years ago .