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good tx poor receive

Posted: 04 Mar 2016, 10:31
by mastercare
Hi all Ive just got back into ham radio, my interest has been 4 metre band using anytone 588 nice little chinese rig problem is after doing some tests i found alot stations hearing me but im not hearing them, unless they were local or strong signals..ok thought anytone was deaf so borrowed an ascom 550 from a mate on same antenna exactly the same...im confused really good tx poor rx the antenna is a 5/8 end fed vertical now on top my chimney ..
some hams think i have a phasing problem? any ideas guys or is it a 70 megs problem?
cheers
paul
g4sbx

Re: good tx poor receive

Posted: 04 Mar 2016, 11:20
by Admiral
Not being facetious, but how do you know that they can hear you when you can't hear them? Or were you on a net?

Re: good tx poor receive

Posted: 04 Mar 2016, 11:36
by Retrodog
70mhz is a noisy band at the best of times,
I'd have thought if your antenna was a problem it would affect your tx signal far more.
Do you have a high level of local noise that may mask weaker signals?

Re: good tx poor receive

Posted: 04 Mar 2016, 14:30
by mastercare
hi thanks for replys, yep we were on a net and i dont seem to have any real noise on 4 metre, im gonna try a home brew antenna weekend, cos i find it very strange..
cheers
paul

Re: good tx poor receive

Posted: 04 Mar 2016, 16:29
by mastercare
Hi yes it was a net...regards noise Ive found the band fairly quiet not much noise,i <did answer this post while i was at work but not sure where it went lol> it is a mystery to me, im going to try a home-brew antenna this week end prob a coax end fed see what reception is like with diff ant...tnx guys for your input, a couple hams think i may have a phasing problem but im not sure...
cheers
paul..

Re: good tx poor receive

Posted: 06 Mar 2016, 08:51
by Admiral
Looks like whoever is approving your posts is too lazy to turn you 'blue'.

Re: good tx poor receive

Posted: 07 Mar 2016, 08:41
by GeeFull
mastercare wrote:Hi all Ive just got back into ham radio, my interest has been 4 metre band using anytone 588 nice little chinese rig problem is after doing some tests i found alot stations hearing me but im not hearing them, unless they were local or strong signals..ok thought anytone was deaf so borrowed an ascom 550 from a mate on same antenna exactly the same...im confused really good tx poor rx the antenna is a 5/8 end fed vertical now on top my chimney ..
some hams think i have a phasing problem? any ideas guys or is it a 70 megs problem?
cheers
paul
g4sbx
I have no idea how the Anytone performs, having never owned one, but can speak for the Ascom 550.
Its a radio that's converted from PMR, and re eepromed, and depending on who set it up, can be sensitive or seemingly deaf as a post.
Couple of reasons for that, often they are fitted with a new eeprom, and very little else is done, bit of a VCO tweek to get them to lock, and into service they go.
They benefit from a full front end re-tune/peak, and also careful setting of the less than sensitive squelch system, which comprises of a menu settable squelch "level", and onboard minimum/maximum sensitivity pot.
If incorrectly set, they can end up seeming a bit deaf, thanks to the less than forgiving squelch sensitivity.
I acquired one years ago, supposedly "all converted ready to go!", PA4DEN Mk3 eeprom and tune up etc. from the RATS amateur radio guys, who converted and sold lot's of these units.
It was deaf as a post on all but strong or local stuff, a front end and IF stages re-tune, and careful setting of squelch threshold, and it was a different radio! ;)
On the antenna, not sure what model it is you are using, I use a simple homebrew half wave end fed for vertical, and never had a problem with it.
Not sure what they mean by a phasing problem, but not unlike 2 metres, just shoving it up in the air can be hit and miss, sometimes just a seemingly small move of location, whilst still at same height, and stations can appear that were initially not heard!
No 70 Mhz isn't persay a problem band, in fact in certain terrains it can and will outperform 2 meters, and as you seem lucky enough to have a low noise floor on it, some find themselves not so lucky, I am sure with a bit more experimentation you can get it up and running with success!
I still have the Ascom, but these days I use a homebrew transverter and an FT817 to drive it, so I can get on SSB as well.
For SSB just using an inverted V dipole, and still have good success with reasonable DX when conditions are favorable.

Re: good tx poor receive

Posted: 07 Mar 2016, 13:55
by paulears
I too have no idea what on earth they mean by 'phasing problem'? The only time phase is an issue is with multiple aerials, with harnesses and matching, but it impacts reception and transmit. I'd guess the receiver may just be a little insensitive?

Re: good tx poor receive

Posted: 08 Mar 2016, 14:09
by mastercare
hi all and tnx fer all ur inputs....well i knocked up a coax end fed ant at the weekend placed it near the the commercial ant same height etc...but same problem peeps hearing me and me only hearing strong ones...results not as good as commercial ant, i take point about ascom i may have worst two evils a deaf anytone which compares to the ascom if its deaf too...also i did some tests with a ham 19 miles from me, we started from 70mhz up at 25khz steps, 70250 he was good 70300 there noisy 70400 good 70450 could not even hear him..so even freqs close give diff results think im gonna send anytone back ive run out ideas...thanks guys for all ur help...
paul

Re: good tx poor receive

Posted: 20 Mar 2016, 11:06
by mastercare
hi all
well just to let u know, the anytone 558 is not faulty, i changed the coax from antenna and results now alot better, prob overkill but used some h100 i had laying around, since used the rig in car and results have been good, here in s/w uk 70 megs is getting very active.
cheers all for advise..
paul

Re: good tx poor receive

Posted: 20 Mar 2016, 13:43
by paulears
That's weird, as before it died off as frequency went up. Still - best not to knock it if the H100 was laying around. I've still got some on one of my aerials here, and apart from being stupidly stiff, it's decent stuff.

Re: good tx poor receive

Posted: 21 Mar 2016, 09:29
by Andy
A friend of mine had a similar problem but his was caused by a high local noise level. Unless your rig has an S meter you can't tell on FM.

Re: good tx poor receive

Posted: 21 Mar 2016, 11:32
by mastercare
Hi all
yep its strange changing coax has made it better, i still get heard more than i receive, but it could be my location, as i say in car out and around no problems rx tx roughly equal. prob never get to bottom of it, but take your point andy.
next step is ssb on 70 megs should be interesting
cheers
paul

Re: good tx poor receive

Posted: 05 Nov 2017, 14:42
by g7ssd
i have an ascom too that seems deaf i also have 2 transverters that i use with a yaesu ft8900 and a yeasu ft897d and find the rx far better

Re: good tx poor receive

Posted: 25 Nov 2017, 11:13
by HFDX
what is your receive bandwidth?