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[polaris]

Dear All,

I am familiar with 27MHz in that I know what range is possible with what trans./rcv. eqpt. I have (aprx. 180yds with good weather/atmospheric conditions), BUT, can I expect less range with 40MHz??? I keep aerials as high and as exposed as possible, and also 'weave' aerials between superstructure enabling as best as possible exposure to the trans. signal both Port & Starboard.

I would be very grateful for opinion/experience on this please.

Regards, Bernard2

[Peterm]

Hi, with a good antenna arrangement, there should be no detrimental effect using 40MH.   I use Hitec 40 MHz and get at least 300 metres with a good line of sight.  PeteM

[DickyD]

I get about 200 yds with my AM 40 MHz.
Haven't tried any further, cant see boat.

Richard

[J.beazley]

Pretty much the same here, Im running 27meg and have had my lifeboat out so far i had a job to see it ::)

getting a 40meg set-up so should be about the same i reckon.

Jay

[John W E]

Hi ya

they normally say for 27 mHz as far as the eye can see - cos dont forget this used to be used by the guys who flew planes as well and they say the same for 40 mHz.  However, since we are dealing with surface craft, the range does decrease in the signal.  But, lets face it, how many of us sail a model at more than 200 yards away from us.   The majority of us sail a model I would say between 20 and 30 yards of us (in distance away).

On the average size model say 4 foot long, at about 20 yards away it doesnt half become difficult to see says he that has a few models that have flat fronts - ah I didnt know that was the side of the lake.

aye
john e
bluebird

[polaris]

Dear All,

Thankyou for troubling to reply so thoroughly.

All that you have said backs up what a knowledgeable friend said the other day, and I am certain that I am being 'concerned' over nothing! It's just that being 'familiar' with 27 one way and another for a long time, the change is a break from the norm. The vessel in question is already fitted with a 40 6ch rcvr., so I won't bother now with thinking about getting a 27 6ch. rcvr.: the vessel needs a min. 4 ch. trans., so I may as well get a 40 and be done with it - all the other ships need only 2 ch. and are on 27, and it's just that I had 'this thing' about wanting to keep things 'standard' across the board!

Is anybody aware of any interference probs. operating 40 vessels at the same time as 27 vessels?

Thankyou again for all your replies.

Regards, Bernard2

[J.beazley]

We had 6 boats on the lake today without any interferance from overhead power lines or the 27meg and 40meg set-ups being used in the models.
The good thing about 40meg also is the amount of different frequency Xtals compared to the few colours you get on 27meg.

get an arangement of 40meg Xtals and your laughing 

Jay

[Captain Anonymous]

A lot of people changed over to 40 Megs because a lot of small toy boats were fitted with a very wide band type 27 meg system, they would come down to the lake , chuck them in and cause havock with the 27 meg boats.

[polaris]

Dear All,

Thankyou again for your helpul replies. The 40 MHg. eqpt. will be for the 1:96 HMS Belfast, so having her on this freq. sounds a good idea in more ways than one.

Regards, Bernard2

[Robert Davies]

I appreciate I'm a bit late to this, but most on our lake have shifted to 40mhz because heavy interference from illegal CB setups :(

I will fully agree with all that have said here that using both 27mhz and 40mhz, my visual acuity fails long before the signal! :)

-Rob

[polaris]

Dear Rob,

I thought 27MHz CB died quite a while ago now? Maybe making a comeback? The 'legal' CB's are on 40MHz I think? - limited to 5w? (or is it 7?).

Regards, Bernard2

[HS93 (RIP)]

CBs are 27 mhz and have never been on 40 mhz

peter

[malcolmfrary]

CBs were on a different part of the 27MHz band, but the ones fitted with illegal "burners" (high powered broad banded amplifiers) could interfere with model control. 
CB in the UK has more or less died from terminal stupidity and the general use of cellphones.  People wanting to use long-distance radio go for the RAE and do it properly, CB walkie talkies are legal for use and not a problem.

[Doc]

Bernard2,
Interference problems can occur on any band, and depends on what happens to be in the general area.  27 Mhz, being an 'older' band, tends to have more possible interference than the others, but, it certainly doesn't always turn out that way.  Higher frequencies are the direction the trend in R/C radios is going.  Doesn't mean there's anything particularly 'wrong' with the lower band though.  Usable range for any of the R/C radio bands is going to be fairly comparable.  Might be some differences, but nothing really outstanding, sort of.  The higher bands can 'carry' more information crammed into a 'channel' than the lower bands (terrible way of putting it, but easier to understand than trying to 'wrap' your mind around baud rates, selectivity, freq.discrimination, timing, and that stuff).
The 'best' R/C radio system is the one you happen to have.  (Unless you can 'sneak' a new on past her!)
 - 'Doc

[polaris]

Dear Doc,

I agree with and appreciate what you say. Back in the dim and distant past (1976), I was 'semi-professional' user (viz. unlicenced Ham), utilising a 27MHz modified unit (wide range SSB etc., etc.), and was only interested in long distance International comms.. I had been told that Hams did not like comms. with non licenced users, but I never found this to be the case, and, when Ionospheric conditions permitted, spoke to many around the World - and others. Other things occurring, my time 'on-air' became less and eventually stopped about 1979, and I must admit that I have forgotten a great deal - just setting the gear up properly now would need a lot of thought and prep.!

Re interference, it was surprising sometimes how powerful trans. from many 1000's of miles could be in high sunspot active periods (1976 to 7/8 being an example - and right now as it happens), and it was interesting to watch the meters record very high RX levels from sometimes a relatively low TX powers from somewhere like Alaska for example (in terms of TX distance/carrier 'bounce' 100w is low, but sometimes even 20w could achieve the same result - though could change very quickly). As I think you know, the Ionosphere is a changing 'sea' and does have a 'wave pattern' so to speak of it's own. So, whilst CB people did correctly get blamed sometimes for causing grief to model users, some of the 'trouble' however could emanate from 1000's of miles away.

As to what Peter said about 40MHz and CB: about 15 years + or so ago the unlicenced/'non-professional' use 27MHz CB freqs. was completely outlawed, but, a 40MHz facility was allowed and licencable - and such eqpt. was available for a time (don't know about now though). I bought a set out of curiosity, used it a couple of times just to see what it was like, found it was not very good and put it back in the box - where it still resides - it goes without saying that I didn't renew the licence! I will look for this gear and double check the freq.. It is interesting to know of a possible 'revival' of 27MHz CB use... such use has probably never completely died out, but it I suppose some enterprising person(s) have imported some gear and maybe trying to resurrect the original 'CB craze' (such eqpt. would probably cost next to nothing to make in China now! - plenty of money was made out of the original craze I am sure.

Anyway, thanks for your reply Doc. - you a Ham by any chance?!

Regards, Bernard2 (I use the 2 as there is I believe someone else with 'my' name on here!!! - on before me thus the 2).

[HS93 (RIP)]

polaris  the standard for the last 10 years has been the 27/81 standard if you had taken your rae you might have learnt a bit about the problems pirates cause, I also think you will find it was 49 mhz  not 40 mhz again a reason  for you to know what you are doing before you jam freqs If you read    http://www.ofcom.org.uk/static/archive/ra/publication/ra_info/ra246/ra246.htm    you might find that the info I gave was correct ... Peter ...G0PAH . someone who took the trouble to learn how NOT to cause problems with emergency services.

[polaris]

Dear Peter,

As to the 'old new' standard, as I said in my last I can't remember and would need to see the unit (in the loft somewhere). Take care in accusing, it's 20 yrs. since I last used the gear (my favourite TX/RX was a Yasu707, but sold this at least 15 yrs. ago to a Ham - don't think Yasu spelt correctly but it sounds the same!), and I have forgotten most of what was learned/taught (back in the days when Morse was the rqmt. to gain a licence... I nearly achieved the required proficiency before I had to move on to other things - seemingly I gather the skill of 'hand typed' Morse is not a rqmt. for a Ham licence now... yet another fallen standard of today's world.

I am well aware that basic 27MHz CB can cause probs., hence my starting this Topic off in the first place - needing helpful assistance to replace what I had forgotten. The SSB freqs. available to me in those long ago days I think ranged from 28 to 32MHz, but I have long lost the calc. tables now, and to be honest I don't think I could do it now anyway! - I have forgotten so much (I had a partic. fad about antennae set up, going to huge lengths to get things as near perfect as poss. - I doing the same thing to my ships now! - one Mayhem member has been a massive help over the last 12mths. in my learning about the refinements of model TX/RX eqpt./principals). The number of years I used the radio eqpt. were enjoyable, and, apart from many overseas Stations, I came to know quite a few GB Hams very well, indeed I still keep in touch with one occasionally (I think a 2 meter follower only now - he talks about using multiple relays etc. to 'get about' - all beyond me!). I was not into 'fixed' stations, choosing remote areas and using mountains to direct where I wanted to go and what I wanted to hear, and this worked very well (about 15 miles remote). Someone I knew in one of the 'Public Services' used to go with me from time to time... he was fascinated by it. To the best of my knowledge I never upset anything, indeed it was easy for me to find this out anyway via my friend - the last I heard of him (about ten years ago), was he lived in the N.East and had a full amateur licence!

Anyway, all this off topic, and must get back to work anyway.

Regards, Bernard2

[justboatonic]

Just to give my twopence worth! US and Europe CB frequencies used some of our 27Mhz channels. When UK 27Mhz CB was introduced in Nov 81 (I think), the UK frequencies were shifted something like 50Khz upwards from the US \Euro frequencies ie almost equivalent to US \ Euro side band frequencies.

This 'shift' was introduced for a number of reasons but the main ones being the UK was already flooded with illegal US 27Mhz CB's plus, there were already legal users of the 27Mhz frequencies in the UK ie RC Modellers and hospital pages etc.

Breaker, breaker!

[malcolmfrary]

Going back to the original question, i.e. range, I find that with my 27MHz set I get about 200 yards with a scrunched up aerial in the superstructure but reasonably well separated from the power wiring.  On the same model with a previous motor and poorer suression, range was less that 100 yards.  The same radio in a yacht, with the aerial run up the backstay, range was 400 yards, and could have been more had I been able to see what was happening out there.
Watching what happens with other people using 40MHz, I have not seen any practical difference with similar layouts.  The important thing seems to be to minimise local interference.

[polaris]

Dear Malcolm,

Thankyou for your Post. As you indicate, motor suppression is all important, and, it seems, it is also advisable to use same with brushless motors as well - &/or motors that are supposed to be 'low emission'. I suppose if one really wanted to go the full hog, coax could be used for power lines etc., but this is not always practicable - and is probably a bit OTT anyway! Aerial position is all important, but with 1:96 destroyers there is not much chance of getting things very high up, however, I have found by threading through superstructure, one can get good all round performance (from any angle), and a range of about 300yds.(which is far enough anyway). It is pleasing to have further confirmation on that 40MHz performance is overall no different from 27MHz eqpt..

Regards, Bernard2

[Doc]

Bernard2,
Guilty as charged.  Amateur, professional, and whatever they're calling that other one now.
 - 'Doc

[polaris]

Dear Doc,

Good for you! A very interesting hobby. A local Vicar around here has been a serious Ham for many years... the Vicarage has an attractive array of arrays!!! He says he is still "trying to find the ultimate frequency"!!! - and won't move because it would take so much work in setting everything up again!

Sunspot activity is at an all-time-high I believe, so things must be 'interesting' at the moment. I wonder if this affects our ships/boats at all? Must do a bit I suppose, but the 'ranges' are so short it's probably negligible.

Regards, Bernard2