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Author Topic: DXing using RTTY  (Read 14807 times)

K1EBU

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DXing using RTTY
« on: July 14, 2015, 08:58:03 PM »

Hello all.  It seems that a lot of the recent Dxpeditions have operated using RTTY. I know several were almost exclusively on that mode. Would have been a couple of ATNOs for me. Have many of you picked up ATNOs using RTTY or some of the other digital modes? I was thinking of purchasing a SignaLink USB at HRO in a couple of days. Setup seems simple. Are there many folks running some of these other modes to DX or would it mostly be used on RTTY? I know the Tx power level must be reduced for long transmissions so is operating RTTY at 50 watts feasible? Efficiency similar to CW? Any thoughts are appreciated. Thanks 73  Gary
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W6GX

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RE: DXing using RTTY
« Reply #1 on: July 14, 2015, 09:27:28 PM »

Hi Gary,

In the past I have worked many new ones via digital modes.  If your goal is to work new ones then yes having RTTY (and all other modes such as PSK31 or CW) is paramount.  Unless you are using RTTY for contesting you could transmit it at 100w with no problems.  The efficiencies of RTTY is quite good however the bottleneck is on weak signals, especially those with polar flutter.  If you are antenna constrained don't expect RTTY to be the savior.  For extremely weak signals there's another digital mode called JT65, which is better than RTTY for weak signals.  For now I would not worry about the efficiencies...having the capability is more important.  You just need to be ready when a new one is available to you on RTTY.  Lastly, RTTY is almost used exclusively by dxpeditions as their digital mode of choice.  However there are quite a number of resident DX'ers who prefer other digital modes such as JT65 or PSK31.  Just the other day I saw VP8LP on JT65 on 80m.  I need VP8/F on 80m.  A signaLink along with the right software will give you all the digital mode choices.  GL.

73,
Jonathan W6GX
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WO7R

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RE: DXing using RTTY
« Reply #2 on: July 15, 2015, 12:27:21 AM »

I have generally found it prudent to run RTTY with reduced power.  It is always recommended and there is a reason for it.  Simply put, it's duty cycle is higher than CW or SSB.

But, while a 3 dB loss is nothing to be sniffed at, it happens that in most cases, the reduction in power does not stop you from making the QSO.  After all, most other operators (the sane ones anyway) are also at reduced power.  CW, because it can still run full power, is a little more reliable, but the difference is often offset by the fact there are still fewer on RTTY than the other modes.

And yes, I have worked several ATNOs on RTTY as the first QSO.  Once in a while, it is even the only mode for a given country.

If you check around, you'll find RTTY has (currently) about half as much participation as CW or SSB.  That said, the overall number of entities available is about the same in the end.  Once in a while, there are still places that don't run RTTY, but even then, so what?  It is the many that do that gives you the extra chances over not doing it.

Still, when something really big time comes on line, RTTY operating can be a challenge, especially as the splits increase.  A lot of software is really set up to deal with a 3 KHz window (SSB, in other words).  It can be managed, but it can also be a pain to manage.

For less rare stuff, the pileups usually stay in that 3 KHz window and the DXing is a little different than either CW or SSB, but overall quite recognizable in terms of figuring out where to transmit to win.

Overall, it's worth overcoming the rabbit fences to get on the air with it.  And, you can manage your separate RTTY score just like you do with SSB and CW.  That has its own charm.

I've been doing RTTY in some form for nearly as long as I've been DXing. Especially for the more modest station, it's a tool that should be in everyone's bag.
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W1VT

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RE: DXing using RTTY
« Reply #3 on: July 15, 2015, 04:32:55 AM »

My first ATNO worked with RTTY was SV2ASP/A on 20M  ;D

I just worked VP8ALJ on 80M JT65 the other night--first of three bandfills on the 13th.

So, yes, it certainly helps to run RTTY, even if you find your most effective DXing mode is CW.

OTOH, I recall impossible pileups filled with heavy hitters--guys on the Honor Roll running big contest stations trying to work a rare station on RTTY with the band wide open.  No chance for the average DXer to get through, even with with DX station booming in.  A difficulty with RTTY and JT65 is the  rate of the DX station--what is your chance of working that VP8 if he only works two or three stations per operating session?  

I recently got a "thank you" email from a Big Gun on 80M JT65--I moved down the waterfall so he could work a rare DX station.  I figure my chances of working the DX are much better if the rare DX actually gets to work someone.  ;)

Zack W1VT

« Last Edit: July 15, 2015, 04:41:54 AM by W1VT »
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LA7GIA

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RE: DXing using RTTY
« Reply #4 on: July 15, 2015, 04:55:57 AM »

I would definitely recommend getting into RTTY if you wanna chase DX. If your radio kan decode/send rtty you don't need a separate interface either.
As for DX purpose I have programmed my FTDX 3000 with 2 buttons on the RTTY remote control:
1. MYCALL x 2
2. 599 599 TU DE MYCALL

I don't need more than those two to log a DX station. I have got several ATNOs this way. So keep it simple.
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VK3MEG

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RE: DXing using RTTY
« Reply #5 on: July 15, 2015, 05:11:34 AM »

i dont operate rtty much but can if need be yes it has bagged me the odd new one but also good for bandfills and marathon points. jt65 is boring but i have been known to indulge . i'm only a 100w pistol so i will take what i can.

if you want to play the dx game seriously you must be preparded to use any mode at any time the key is having you station set up so you can fire a shot quickly b4 the pile up builds my ic 7100 has  a built in rtty keyer and decoder. its come in handy a few times i also use dx labs winwarbler.
i'm well over 100 countries worked in cw and i only started late last years about 50 in digi modes soon i will have dxcc in ssb cw and digi modes :)
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N3QE

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RE: DXing using RTTY
« Reply #6 on: July 15, 2015, 06:40:38 AM »

There are some good reasons to chase DX on RTTY. There are a couple of entities that have a prolific RTTY operator who uploads to LOTW quickly, vs the non-RTTY operators that do not upload to LOTW.

For some small or single-op DXpeditions, they might not do any CW but they might do RTTY. The phone pileups are a zoo, but the RTTY pileups tend to be smaller.

Some DXpeditions have exceptionally poor RTTY technique, either using PSK31-style brag files or sending calls only once at start or both. These are the exceptions rather than the rule but they are sore points for experienced RTTY ops, and I guess we just have to live with it.

Very commonly, the callers for a DXpedition have poor RTTY technique. This can be an advantage if you have good technique - you can be in and out in just a minute while all the other bozos are just continuously sending their call without listening.

I think there's a couple misconceptions running around:

Not necessarily true that you have to run at lower power. In many rigs barefoot, the final dissipation is pretty much the same no matter whether you are running 50W or 100W. If running with e.g. an 811A based amp, many of these are quite capable of 7-second transmit bursts at near full power without inflicting any damage on the tubes at all. Now,this is assuming that you work a pileup by mostly listening and occasionally transmitting. If you work a pileup by just sending your call continuously for half an hour, you are not going to make the QSO anyway no matter how much power you use!

Splits do not have to be confined to audio passband. All rigs have a split feature that works just fine in RTTY.
« Last Edit: July 15, 2015, 06:43:01 AM by N3QE »
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WO7R

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RE: DXing using RTTY
« Reply #7 on: July 15, 2015, 07:13:40 AM »

Quote
There are a couple of entities that have a prolific RTTY operator who uploads to LOTW quickly, vs the non-RTTY operators that do not upload to LOTW.

This is a stronger point, IME.

Since about 2004, a bit more than half of my DXCC Challenge confirmations have been via LOTW.  In other words, "the ones that count", not just any old QSO, have been half LOTW.

However, the percentage of RTTY confirming via LOTW is about 70 per cent, which is well above CW, at least.  This may be statistical flux of some kind, as SSB is closer to RTTY, but none the less, I have noticed that two classes of hams -- RTTY hams and contesting hams -- that seem disproportionately likely to use LOTW.

So, if you get the same "new one" via RTTY versus some other mode, and if you don't care to confirm absolutely everything, RTTY gives you a modest financial advantage.  And, a great deal more certainty.
« Last Edit: July 15, 2015, 07:16:07 AM by WO7R »
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N3QE

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RE: DXing using RTTY
« Reply #8 on: July 15, 2015, 07:18:57 AM »

However, the percentage of RTTY confirming via LOTW is about 70 per cent, which is well above CW, at least.  This may be statistical flux of some kind, as SSB is closer to RTTY, but none the less, I have noticed that two classes of hams -- RTTY hams and contesting hams -- that seem disproportionately likely to use LOTW.

Excellent point!

Note that a lot of the PSK31 crowd for some reason does eQSL and does not do LOTW.
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WO7R

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RE: DXing using RTTY
« Reply #9 on: July 15, 2015, 07:21:38 AM »

Quote
In many rigs barefoot, the final dissipation is pretty much the same no matter whether you are running 50W or 100W.

Yet, that is not what the various rigs manuals say.  Please point out the ones that have the same power rating for RTTY and SSB.  I can't recall seeing any, nor would I expect to see them.

It is true that if you run the full 100 watts, your rig (usually) doesn't burn up at once.  Everyone makes that mistake and rigs don't fry quite that easily.  But, especially with solid state finals, you are asking for a lot more heat to be removed and your overall duty cycle is much higher.  Even if your duty cycle overall seems low, as you are not transmitting continuously, it is higher "when it counts" -- when transmitting.  And, it is heat that is the enemy of solid state devices and their lifetime.  Specifically, getting heat away from the various "junctions" within the chip.

Moreover, modes like JT65 run for 48 seconds, not seven.  

I have owned rigs which cannot even do 50 per cent power for JT65.  They key?  If your power output fluctuates, you're asking for more than you should be.
« Last Edit: July 15, 2015, 07:24:22 AM by WO7R »
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K1EBU

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RE: DXing using RTTY
« Reply #10 on: July 15, 2015, 07:41:20 AM »

Thank you for your replies. I am going to make the trek to HRO tomorrow. You made some good points. I should be prepared to work the modes that they work. LotW confirmations are a good thing too! 73
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N3QE

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RE: DXing using RTTY
« Reply #11 on: July 15, 2015, 08:27:59 AM »

Yet, that is not what the various rigs manuals say.  Please point out the ones that have the same power rating for RTTY and SSB.  I can't recall seeing any, nor would I expect to see them.

My Ten-Tec Eagle is rated for 100W in heavy RTTY use (proven by tens of thousands of RTTY contest QSO's). I know the IC-7410 is also rated for 100W in RTTY use.

And again, the duty cycle for RTTY when chasing DX, will be substantially less than the duty cycle for RTTY when contesting.

I do not feel qualified to talk about JT65 - no experience. I know the 7 second RTTY "callsign twice" cycle is short enough to be acceptable by any rig I know at full power, because the thermal time constant of the heat sink is going to be far longer than that. The 48 second JT65 cycle, that may be (especially for small rigs originally designed for mobile use) comparable to the thermal time constant of the PA+Heat Sink.
« Last Edit: July 15, 2015, 08:30:30 AM by N3QE »
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AA4PB

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RE: DXing using RTTY
« Reply #12 on: July 15, 2015, 08:41:58 AM »

Some transceivers are rated for 100W continuous duty which means you can run 100W on RTTY or SSB or CW. However, many transceivers are rated for 100W intermittent duty SSB and CW and require you to reduce power output for a 100% duty cycle mode like RTTY.
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Bob  AA4PB
Garrisonville, VA

KD0PO

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RE: DXing using RTTY
« Reply #13 on: July 15, 2015, 09:02:47 AM »

a key with RTTY if using "AFSK" is to reduce the audio input "mic amp" way down. It is very easy to over drive the solid state finals in a transceiver and blow your PA.

I love RTTY, with my hearing deficit, it makes easy copy to just read off the screen.
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K5NOK

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RE: DXing using RTTY
« Reply #14 on: July 15, 2015, 09:58:17 AM »

I have just started using RTTY.
I am using a TS 590SG with a USB cable to my computer and MMTTY.
The trick using AFSK is adjusting your sound card level so that the ALC only shows 1 or 2 pips on the radio meter.
I was excited because my second RTTY contact was with United Arab Emirates on 20 meters.
This wasn't an ATNO but a nice contact since he jumped on made 4 or 5 contacts and disappeared.
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