Range tests

[Rich Griff]

Some very interesting comments are being raised on Toto's thread about his model aircrafts "refit".

 

To prevent more drift on his thread, interesting as it is, could a more "in depth" airing of views take place in this thread.

 

My cheapo internet phone will not "copy and paste", my photos are crap and I still need to learn how to insert quotes, so perhaps a good starting point fir this thread and topic would be what our "Bible" says about this subject ( range tests ), the bmfa guidance book ?

 

However, may I start by saying "a stitch in time could save £900, and a huge court case ! ".

 

Over to you guys...

 

 

Edited September 17, 2023 by Rich Griff

[Ron Gray]

Leccy had posted these in 'tother thread:

 

Here's what the BMFA handbook says.

 

13.4 Pre Flying Session Model Checks

On arrival at the flying site:

(a) Check airframe for any transit damage.

(b) Check that servos and linkages are secure.

(c) Check undercarriage for secure fixing and correct alignment.

(d) Check propeller for damage and secure fixing.

(e) Check receiver aerial for damage and, with 2.4 GHz equipment, that the orientation is correct.

(f) Carry out a range check if any changes or re-installation of equipment have taken place since the last session or if a history of range problems exists. 

(g) Carry out a failsafe check and make sure that it does what you expect.

(h) Check that the receiver and transmitter batteries have sufficient capacity for the intended use.

 

Here's what the BMFA Technical Annexe has to say about range checks .

 

3.22 Transmitter and Receiver Issues

 

With new or repaired radio control equipment, a ground range check is essential, preferably in a model and with the model's engine running if possible. Check the manufacturer’s literature or website for guidance on your transmitter or, if this is not possible, look for a minimum range of between 30 and 50 metres with the transmitter aerial down and no servo jittering. 2.4 GHz equipment usually has a ‘range check’ button that enables a ground range check to be done, even though the aerial cannot be altered. It is recommended that you make use of this facility regularly so that you can monitor the performance of your radio. It is good practice to carry out a routine range check on your equipment at regular intervals, at least every month or so, and a check is advisable if you have not flown for a few weeks. You should also be prepared to do a range check if you feel that you have a problem with your radio equipment or if you have removed and replaced crystals or a transmitter module. If the model has a spark ignition or electric motor then the range check should always be carried out with the engine running.

[EarlyBird]

7 minutes ago, Rich Griff said:

My cheapo internet phone will not "copy and paste",

Have you tried?

[Ron Gray]

My own view, as expressed in the other thread, is that it takes very little time to do a range check for each model at the start of a flying session so why not carry it out, there is nothing to lose and perhaps lots to gain from it! An exercise in risk reduction.

[gangster]

For years I have always range tested models at the start of every session. I lost my thoroughness on this one when after range testing with an FRSKY module in a TX. I inadvertently left it on low power, no warning on the mode I was using. I consequently went out of range and it cost me a new Hanger Monkey on its maiden flight. A lovely flyer it was too. But in reality I am a big advocate of regular range checks. I have little time for all the excuses, interference etc from people who never range check

[PDB]

If on your own is it ok to range test with the model on the ground or on a table?

Edited September 17, 2023 by PDB

[Cuban8]

12 minutes ago, PDB said:

If on your own is it ok to range check with the model on the ground or on a table?

If it's electric, then providing the model is thoroughly restrained then I don't see a problem. I range check with the model on the ground to make the test more of a challenge for the system.

I have a very large garden and am able to have the model 50M from the tranny.

Even on reduced power I find the connection remains solid so any change to that will be noticed. We have a large Eucalyptus at the bottom of the garden and putting the tranny behind that will kill the reception at the model stone dead, even on full power (water content of the trunk, probably). I also found that during range test experiments, holding the tranny behind my back, next to my pelvis will also block the full power signal just as effectively. 

Bearing this in mind, I'm very careful when flying with a number of other pilots on the flightline to always make sure that my tranny is not blocked by someone else's body.

 

[Ron Gray]

Not sure about other radio manufacturers but FrSky have this in their Rx notes

 

 

Of course you may not have something to place the model on so on the ground is OK, in fact I’ve tried out range testing with the model on the ground and then with it on a table, it made very little difference. One thing I would say and that is for a ‘proper’ range test you should get someone to rotate the model, horizontally, through 360° and I admit to only doing that with a newly built model. 

[Dickw]

I leave the Tx on a table with it cycling a servo, then walk away carrying the model. That way I can rotate the model through all angles and even place myself between the aerials and the Tx to check for any blind spots. 

I try to do every range test in the same way/location so I can spot any unexpected behaviour.

Every new or "re-installed" model gets a full range check, but I only do repeat range checks occasionally as I have found telemetry for signal strength and quality to be very useful on a daily basis.

 

Dick

[Keith Berriman]

I have Hitec equipment and find if I do not do a full shut down of the tx& Rx I do have problems

Just switching from range check to full power on tx and then fly is problematic

The model is unstable done this twice on different occasions so it's full power down

[Brian Cooper]

Just for jollies, a pal and myself sometimes do "old school" (real world) range checks. 

 

There is a place locally where we do it and it is at either end of a valley, with a clear line of sight between the two high sides. . The distance is almost a mile. 

 

One of us stays with the model while the other one drives off to the other side. 

We keep in touch with walkie talkies. 

 

Spektrum radio has very good range.. 

[Phil Green]

My own unpopular view is that range checks should be full power, full range. Take as an example what seems to be the most popular brand out there, with it's notorious history of RF board failures. A low-power, 50-pace check is almost worthless.

It's not a popular opinion but...

 

 

[GrumpyGnome]

When i do a range check, I do a reduced power check, and a 'full power walk as far from model as possible' check.  I always do it with the model tethered on the ground with the engine/motor running.  I also keep an eye on the telemetry signal strength. 

 

I also do the opposite and put the tx on the ground, with a bit of throttle, and walk the model away, changing it's orientation. 

 

If failsafe kicks in, then the range check is failed.    

[leccyflyer]

3 hours ago, Rich Griff said:

Some very interesting comments are being raised on Toto's thread about his model aircrafts "refit".

 

To prevent more drift on his thread, interesting as it is, could a more "in depth" airing of views take place in this thread.

 

My cheapo internet phone will not "copy and paste", my photos are crap and I still need to learn how to insert quotes, so perhaps a good starting point fir this thread and topic would be what our "Bible" says about this subject ( range tests ), the bmfa guidance book ?

 

However, may I start by saying "a stitch in time could save £900, and a huge court case ! ".

 

Over to you guys...

 

 

Once again, you didn't answer the question I asked in that other thread. 

 

I'd be interested to know when you last actually did a range check.

[leccyflyer]

2 hours ago, gangster said:

For years I have always range tested models at the start of every session. I lost my thoroughness on this one when after range testing with an FRSKY module in a TX. I inadvertently left it on low power, no warning on the mode I was using. I consequently went out of range and it cost me a new Hanger Monkey on its maiden flight. A lovely flyer it was too. But in reality I am a big advocate of regular range checks. I have little time for all the excuses, interference etc from people who never range check

Yep, I did exactly the same thing on my first flight with Frsky, as the procedure differed from the Spektrum, which restored full power on releasing the button. I'm careful now when range checking to completely cycle the power after the range check.

[EarlyBird]

3 hours ago, Rich Griff said:

However, may I start by saying "a stitch in time could save £900, and a huge court case ! ".

Rich, How will a range check do that?

[gangster]

1 hour ago, Phil Green said:

My own unpopular view is that range checks should be full power, full range. Take as an example what seems to be the most popular brand out there, with it's notorious history of RF board failures. A low-power, 50-pace check is almost worthless.

It's not a popular opinion but...

 

 

Yes but on the other hand some 2.4 aerials, both TX and Rx are a bit flimsy.  Added to that a number of fliers are quite brutal to them twisting them around to play with orientation. A low power range check would likely show this damage up

[Ron Gray]

1 hour ago, leccyflyer said:

I did exactly the same thing on my first flight with Frsky

All my FrSky Tx emit a horrible beep when in range mode, something you just don’t ignore! Don’t know about FrSky modules in other kit though.

 

1 hour ago, EarlyBird said:

Rich, How will a range check do that?

Not sure about the court case but potentially saving a model because it failed a range test  then yes.

 

1 hour ago, gangster said:

A low power range check would likely show this damage up

I had exactly that a couple of years back where the range checked showed very low signal strength having only walked out half the checking distance. Upon investigation one aerial had partially broken away from its clip, replacing it with a new one solved the problem.

[gangster]

24 minutes ago, Ron Gray said:

All my FrSky Tx emit a horrible beep when in range mode, something you just don’t ignore! Don’t know about FrSky modules in other kit though.

 

Not sure about the court case but potentially saving a model because it failed a range test  then yes.

 

I had exactly that a couple of years back where the range checked showed very low signal strength having only walked out half the checking distance. Upon investigation one aerial had partially broken away from its clip, replacing it with a new one solved the problem.

The module emits a polite bleep, but not in all modes

[leccyflyer]

Yep, my module certainly never gave a loud warning. In fact I'm not even sure it beeped - I only noticed after the crash that the light was flashing. That was a MK 1 module, since replaced with a later version.

[MattyB]

The early module based FrSky systems were very quiet, so launching in range check mode was a relatively easy mistake to make - I didn’t donut myself, but my Dad managed it at least once, and was lucky to get away with it. Thankfully all the Frsky TXs are much more vocal in this respect, so it’s not something that would ever happen  with one of those. 

[Andy48]

With a new setup, I do a ground range check, its usually a long walk. Then being a Frsky system I do a couple of test flights and examine the range telemetry data afterwards. This tests the model on full power and in all orientations.

Incidentally being Frsky, you get a warning on every flight if there is a range problem.

[Phil Green]

1 hour ago, MattyB said:

... I didn’t donut myself, but my Dad managed it at least once

ah Dads & donuts, always in a jam eh Matt!  😁
 

[Cuban8]

21 hours ago, Phil Green said:

My own unpopular view is that range checks should be full power, full range. Take as an example what seems to be the most popular brand out there, with it's notorious history of RF board failures. A low-power, 50-pace check is almost worthless.

It's not a popular opinion but...

 

 

Ever since the days of 27 and 35Megs, range checks have been essential and the basic process hasn't changed. Old style aerial collapsed or with 2.4, a button to be pushed or a setting switched to attenuate the radiated signal. A rather rough and ready approach that can catch certain problems but will most certainly miss quite a few others. Whether that's "almost worthless" I wouldn't like to say.

I'm not familiar with all radio brands and models of radios and I would guess that some radio transmitters are equiped with a proper diagnostic tool that tells the operator when the radiated signal is not correct. My old DX7 has no indication as to whether its transmitting or not and I think my DX8G2 lights its orange indicator to say that RF is being transmitted. No indication as to how well though.

I wish manufacturers would include a proper diagnostic tool that will give the operator confidence in the strength of signal radiated. How difficult or expensive would that be to include on a mass produced product?

 

 

[GrumpyGnome]

4 minutes ago, Cuban8 said:

I wish manufacturers would include a proper diagnostic tool that will give the operator confidence in the strength of signal radiated. How difficult or expensive would that be to include on a mass produced product?

 

Unless I've misinterpreted things, a number do include them - my Radiomaster and Taranis have all sorts of signal strength gubbins..... don't Spektrum, for example, gather telemetry about fades, frame losses etc.....?