Bryan,
Sorry I'm coming into this late.....but I believe I've read most of the postings here, the pertainant ones anyway...
Quote:
Originally Posted by bcripps
In the Bahamas, I could get Chris Parker's weather forecasts reasonably well (he broadcasts from FL), though I could never hear the boats responding to him on their SSB radios. He could. Now, in the Dominican Republic, he sounds like he is broadcasting from his shower. The noise is such that his broadcast is unreadable.
What I can't understand is why I'm the only person in the harbor who can't receive Chris Parker's weather forecast each morning. I was lead to believe that the Palstar Radio is a top end receiver. Other boaters are using the ICOM SSB radio and are having no trouble. I am at anchor in Luperon's harbor in the Dominican Republic and it is not overly crowded. But this problem didn't start here. I have never been thrilled with the performance of my system since installing it over two years ago in Florida. Initially, in the Bahamas, I could copy Chris Parker's signal but could never hear the boats responding to him. Not unless they were anchored very close to me... within two or three miles!
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Bryan, distance and time of year has a BIG affect on
HF Radio communications...
AND, the Palstar is not a
communications receiver...but rather it's really a SW receiver....and is not the unit I'd recommend....(but, we need to deal with what you've got...so here goes...)
See details below.....
In addition to Bill's excellent comments on on-board noise and daily/hourly propagation changes.....
Perhaps I could add a few more things that will help...
1)
a) You're in Luperon, DR....surrounded by hills as well as all sorts of RF Noise (from both other boats, as well as a lot from shore)....
Chris Parker is on shore, inland, in Lakeland, FL....
About 750nm / 850sm away....
b) Chris' limited coast station
license limits him to 150 watts of transmitter power....
And, I'm not sure what Chris is using for antennas on 4mhz thru 8mhz, but I doubt it is any type of "hi-gain" antenna...
c) The Palstar receiver isn't that great of a receiver...marketing be damned....your typical a 25-yr old mid-priced ham HF rig has a better reciever!!!!
Notwithstanding knowledgeable comments otherwise, it's really not designed to be a hi-quality
SSB receiver....more like a general coverage utility / SW receiver....
(I know the
marketing team touts the "world famous Collins mechanical filters", but please this is the 20th Century...opps, 21st Century....and there was MUCH more to the early 60's Collins 75S-1 and the older 75A-4, R-390's, etc. then their "mechanical filters"!!)
Quite honestly, you'd be better off with a old, used Icome IC-735 HF transceiver ($250 - $300), than the Palstar.....
{Of course, my favs are my Drake TR-7's....but I digress...}
No RF Gain control, and a pretty poor design to start with, makes this unit a poor choice for low-band weak-signal
work and/or for hi-RF environs!!!
(but it IS marketed well!!!)
And, understand that most SW Broadcast stations use > 100,000 watts of transmitter power into directional / gain antennas, and use freqs optimized for the communications path and time of day, etc....
And, most of the stronger SW Stations are ~ 500,000 watts.....
THE USCG Weather brodcast transmitters are 1000 - 4000 watts....
The strongest ham signals on 40m (say 7268khz) are 1000 - 1500 watts, and some may have gain antennas....
Chris Parker has a 150 watt transmitter output....
So, even slight noise that wouldn't effect stronger signals, can mask the weaker signals....
d) Summertime low-band HF (< 10mhz) comms in the
Caribbean / SE US, is tough sometimes!!!
Sorry about that, but even with the daytime D-layer absoption....the atmospheric noise can be quite high....and T-Storm static even in the daytime can be a bear....
e) You make no mention of attempting to receive Chris on 12mhz....only 4mhz and 8mhz....
4mhz is going to be a very difficult feat with your path and time-of-day....but 8mhz should be doable (depending on noise and that day's propagation)
2) So, combine the ~ 850 mile path a couple hours after sunrise, in the summertime, on 4mhz, with non gain antennas, and the transmitting station > 100 inland along the path.....and the reciving station in a harbor surrounded by hills w/ lots of RF noise around, etc...
And, the fact is that 4mhz is going to be a tough freq to use for that path, time of day, etc. even with great
equipment....
Add in the limited transmitter power, and the lower-quality receiver, and I'd be surprised if you heard Chris on 4.045mhz....
And, I'm not clear whether the other boats that you hear communicating with him on 4mhz are there in Luperon with you???
I suspect those he's communicating with on 4mhz, are 400 - 600 miles CLOSER to Chris than you are, and the ones there in the DR are using 8mhz (or 12mhz)???
[Note however, for daytime comms on 4mhz, your longer "inverted-v"-type antenna (fed directly to the receiver's "long-wire" antenna jack, NOT thru any un-un) is going to be a decent antenna....and should even
work well on 8mhz, although I'd shorten it by half and see how that works on 8mhz and 12mhz...
Understand that for daytime skywave comms on these lower freqs, you are dealing with very high radiation angle signals, as the lower angle signals are usually completely absorbed by the "D" Layer of the ionosphere....so using a longer horizontal antenna is a good choice, but 4mhz just isn't a good choice for this path, time of day, etc...
Depending on the day's
solar flux and geo mag activity, 7-8mhz is about the upper limit of NVIS comms, and 9-10mhz is usually the lower limit of summertime low-angle comms....BUT, I see 7-8 mhz supporting 800-1000+ mile daytime paths, especially early AM....and I've seen 12mhz with very high D-layer absorption, esp. late afternoon....so things are not always the way the "science" says they should be...
]
You must understand that while daytime skywave comms is possible on 4mhz, your ~ 850 mile path, is way beyond the "normal" distances, and "D" layer absoption is going to be quite high, as well as significant ground losses on Chris' end.....
8mhz would be one of the bands to use for an early to mid-morning ~850 mile path....and depending on that day's propagation, 12mhz may also be a good choice (perhaps even a better choice....)
Have you tried lisetning for Chris on 12.350mhz at 1315z???
And, FYI, Chris' main customer base are the "coastal" and "near offshore" cruisers....mostly within 500 miles from S. Fla (most in the central Bahamas)....and as such he has limited time to spend on 12mhz and 16mhz, where stations from 600 - 2000 miles would typically be contacted....
3) I wrote a quite detailed post regarding freq choice for specific paths, etc....
Have a look here...
SSCA Forum • View topic - HF Radio Freqs, summertime Atlantic crossing, offshore Net..
And, you may also find this one helpful...
SSCA Forum • View topic - Tips for using an HF-SSB Radio (mostly for newcomers)
4) Bryan, these bits of info are VERY telling!!!
Quote:
Originally Posted by bcripps
I've been faithfully at the radio controls every morning and have little to show for it but a weak battery. I've had mixed results tuning in NMN on 6502 & 8765, by the way, and Chris Parker remains elusive. It shouldn't be this hard.
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a) I hope you are using a good pair of communications-type headphones???
NOT the radio's speaker.....and NOT some fancy "noise-canceling" headphones or DSP speaker, as they'll do nothing, but usually make matters worse!!!
There is very little that gives the bang-for-the-buck that a good pair of headphones (and a little experience) do....
(while I personally like my Kenwood HS-6 phones.....there are others that work well!!!)
b) You should NOT need to be fuddling with the radio controls much at all.....
Once you've set the gains, just sit back, listen, and maybe occasional rf gain adjustments....
But, the Palstar doesn't have an RF Gain control, and after you've set it for USB (and its nominal 2.5khz IF Bandwidth), dail-in the correct frequency, all you can do is adjust the volume....
c) The GOOD news here....
You may in fact have a defective receiver....as NMN tranmits on 6501 and 8764 (as well as 4426, 13089, and 17314), not 6502 and 8765.....
This is a VERY telling piece of info....
And, you should have no problem hearing NMN on 13.089mhz, ~1300 miles north of you....midday and late afternoon....
Have a look at NMN and NMG broadcast schedules....
USCG HF Voice
Also, don't forget to have a listen to WLO's traffic lists (top of each hour) and weather broadcasts....
HF SSB Radiotelephone, Telex and Email Frequencies and Channels
Bottom line:
From the DR, if you can't hear NMN, NMG, and WLO, on 12/13mhz and 16/17mhz daytime (and probably 8mhz in early morning), using a simple ~ 30' length of wire strung up a halyard, then you either have a defective receiver, or a LOT of local RF Noise masking the wanted signals!!!!
And, as I wrote above.....Summertime low-band HF comms (< 10mhz) in the
Caribbean / SE US, is tough sometimes!!!
Sorry about that, but even with the daytime D-layer absoption....the atmospheric noise can be quite high....and T-Storm static even in the daytime can be a pain....
So, please be sure to choose the freq/band that best suits the path, time-of-day, and propagation (and atmospheric) conditions....NOT just what other boaters may tell 'ya....
Quote:
Originally Posted by bcripps
I might try pulling out my old Panasonic RF-B65 portable, the radio I set out with on my first sail to Guatemala. That was some thirty years ago. Chris Parker was probably still playing with his crystal set. In those days all we had was NMN and “Herb” on Southbound II, out of Bermuda.
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5) Bryan, this is a GREAT idea....and is also telling, in that you should know a bit of what I wrote above....
{BTW, I've been doing HF comms (both on-shore and at sea) for almost 40 years now....}
Quote:
Originally Posted by bcripps
I believe I've eliminated any chance of on-board noise.
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6) You probably did eliminate most....but don't be 100% sure....there is a wide range of odd things that can cause RFI.....
See my other posts for dozens of thoughts.....
But, here's a recent experience of mine...true story!!!
I recently discovered a new RFI source!!! The digital clock in the new microwave I installed last fall (replaced an old one)....I don't use the micrwave much (powered either from
shore power or genset), and I'm very rarely plugged-in to
shore power.....
But, a couple weeks ago I plugged-in for a few days to run the Air Cond and do some clean-up, etc...and wouldn't you know it, I found a couple very low-level, odd RF noises on HF.....even with "everything on-board turned off", including battery
charger, and ALL 12vdc systems except for my M-802, I still had the small RF noises.....
Swtiching the AC breaker for the microwave off....No RF Noises....
Swtiching the breaker back on....RF Noises.....
And the "odd" part, throwing a bag of popcorn in the microwave, and popping it.....the same minor RF noise as just having the unit plugged-in (and of course it has a nice digital clock / timer, and a microprocessor, etc.....so there's my noise source!!!)
This presents no real issue for me, as I rarely am plugged-in and rarely use the microwave....and certainly will be able to coordinate any microwave use around my HF operating schedules!!!!
Bryan, I understand that my microwave is NOT casuing your HF receive issues.....my point here is, that after ~40 years of
HF radio experience, and 8 years on my
current boat, I can still be surprised by what crops up unexpectedly!!!!
So, have a look around for a kitchen/galley timer.....a stopwatch....a digital
alarm clock....maybe a "smartphone"....or an i-Pod.....or any number of 100's of odd things that could be a cause of high receive noise levels.....(it could even be something on-shore or on another boat....so MOVING your boat a 1/2 to 1 mile away for a few hours....or even go out for a day-sail....is always a good idea!!!!)
Quote:
Originally Posted by bcripps
There can't be anything wrong with the antenna; it's a piece of wire!
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7) Yep....no antenna issues!!
Quote:
Originally Posted by bcripps
Inexperience? Well probably, but I know how to twiddle a knob. So that leaves the radio:
Either the Palstar receiver isn't as good as everyone seems to think or the one I have is defective. I agree the quality of sound is very impressive from the Palstar and it works quite well on AM but if it can't pull in the USB & LSB signals, then it isn't much good as a boat radio.
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8 ) a) Don't be too hard on yourself, regarding inexperience.....
Experience comes with time...there is no magic bullet here....
But, to be clear, there is a LOT more to optimal use of HF communications than twiddling knobs.....
Starting with choosing the correct freqs/mode, for path, time-of-day, time-of-year, etc.....to choosing the correct antenna....to choosing the correct receiver....to reducing the receiver's gain or increasing the AGC threshold, by turning the "RF Gain control"....making sure you are not ruining your receiver's performace by using a poor noise blanker, etc. etc. etc....
The list goes on and on.....
And, it is this list that makes many of those new to HF comms step back and say "gimmie a sat
phone..." as they simply don't wish to invest the time (a few weeks / a month) to learn the nitty-gritty, and would rather invest the $$$$ instead....
b) And, while I suspect that AM Broadcast and SW Broadcast sound good
on the Palstar, I'm wondering why some sell / market it otherwise....
I mean, it is NOT a hi-quality SSB receiver, it isn't even an average quality SSB receiver.....in my opinion, it's a below average SSB receiver.....although this is MY opinion, you can look at its design / specs / features, compare it with other receivers (or transceivers) and see for yourself....
Quote:
Originally Posted by bcripps
Bottom line: if I ever get back to the US, I'll be buying an ICOM.
Again, thanks to you and to everyone else who shared their knowledge, ideas and good wishes.
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9 ) Nothing wrong with an "Icom"....just make sure whatever model you buy, actually works BEFORE you pay for it!!!!
I REALLY do hope this helps....
John
s/v Annie Laurie
P.S. Understand that the Palstar is basically a Shortwave receiver.....Not designed to be a "communications" receiver.....(my opinion it's a decent $150 SW receiver....and that's it....
And, while some
reviews of the Palstar are positive and some negative.....
Here's a review (from last Jan) that may highlight an issue or two....
It is a mystery to me how it can be so highly rated. My best guess is that Palstar has quality control issues, which they are in denial about. If you get a plum radio, perhaps it can be quite good. (But why would anyone want to take their chances? There's other options out there.)
Or maybe it's that most people only listen to shortwave in noisy urban environments, which mask most of the birdie problems that plagued my R30A. I was not aware of the problems my set had until I took it into a remote area when camping.
All went fine on my first backwoods listening session, until I chanced to listen to Radio Australia late in the night on the 22m band. “That’s odd,” I thought to myself. “It sounds like I’m picking up my roommate’s computer, yet I’m at least twenty miles from the nearest PC.”
Not having any way to back up my suspicion that there might be something wrong with the R30A (it was the only shortwave receiver I had with me at the time), I made a note to investigate the matter further when I got home.
What I found is that my R30A had horrible birdie issues. Only a few of them were strong, but most of them had a warbling character to them which makes for a most annoying background noise unless one is listening to a strong signal. The signals are audible even with no antenna connected to the R30A. Even more damningly, they are audible on my Lowe HF-150, and when I turn the Palstar off, the birdies vanish from the Lowe as well.
On my second camping trip, I take both the R30A and the HF-150 along. The unpleasant truth soon becomes apparent as I listen to the Voice of Russia on 13775 kHz, which happens to be one of the places where the R30A has a weak but definite birdie. At first, it’s a strong signal and perfectly listenable, but it starts fading out. At that point, a most annoying high-pitched warble starts becoming all-too-apparent.
I switch to the HF-150 and tune to the same frequency. A weak signal with some static hiss in the background, but it’s completely listenable now that the annoying warble is gone.
On the quality control issues, the set I received made no sound when I first turned it on. Opening it up revealed that the speaker had never been connected. It was a simple matter of plugging in the speaker connector to the proper location to fix this problem, but it does point out that Palstar has QC issues -- even the most basic power-on test would have uncovered this problem.
And, another from a month earlier....
After a year or so of exploring this set I was at despair to get rid of its internal signal generation putting sigs all over the bands and over ones I wanted, together with low sensitivity.
Finally decided it must be the first mixer balance so took to this and with aerial shorted tuned it for a signal null (lowest noise) then put on the aerial and on a weak signal very carefully tweaked it for best response within the null area. No instruments, just by ear.
Ok so that fixed it! Now it's the most sensitive set I have below 2 mhz and works a treat on all other bands. the internals are now so low as to be of no consequence.