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eHam Forums => CW => Topic started by: AC2EU on March 24, 2013, 01:08:26 PM



Title: Does anybody zero beat a QSO anymore?
Post by: AC2EU on March 24, 2013, 01:08:26 PM
As a fledgling CW Op, I spend a lot of time attempting to copy live QSOs as practice.
My receiver BW is about 500Hz in CW. Even so, some operators are so far off that I have to re-tune to hear the responding station who may be on the top or bottom edge ( or beyond) the BW!
What's up with that? BTW, I'm not talking about splits here, just a normal QSO.

Is it considered impolite to ask the responding station to zero beat your frequency? The ops I've heard just seem to ignore it.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K0OD on March 24, 2013, 01:50:19 PM
The panadaptor on my Flex-5000 clearly shows the positions of CW stations in QSO. Most are almost precisely on top of each other... within 50 to 100 Hz. 

I also work some QRP with my OHR-100 transceiver, a $150 kit which uses varactor tuning. Getting within 500 Hz is a chore. Its native receive bandwidth is about 1 KHz and the varactor tuning can jump around. I've learned to use an outboard audio filter to get closer to stations I call. Note that some QRP transmitters still use crystal control.

Quote
I've heard just seem to ignore it.

Right. When I got in the hobby novices were lucky if they owned 3 crystals. You called CQ and tuned up and down maybe 20 kHz for replies! Even now not everyone is using a state of the art radio. I'm certainly not going to criticize some Cuban who made his equipment from a 1956 Chevy. Or a guy who's drifted due to problems at his power company. On 160 you may be hearing boat anchors.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: AC4RD on March 24, 2013, 01:52:16 PM
Jim, I always try to get as close to zero-beat as I can with my poor old ears--if the DX is working that way.  Some times you hear DX working simplex but coming back to stations that are a couple of hundred off.  I think sometimes that's their way of narrowing the pileup without going to split operation--pick a guy 300Hz up, and then one 200Hz down.  I think with a narrow filter that might help.

But yeah, aside from that, I generally try to get as close to the station I'm calling as I can.  Like you, I see folks who aren't as successful at it. :)


Title: RE: Does anybody zero beat a QSO anymore?
Post by: NO2A on March 24, 2013, 04:18:59 PM
Yaesu has a feature that works good. When you have tuned the cw signal in properly,the mutifunction led on my FT-857 will glow blue. It works with weak signals too. Not sure if their other rigs do this.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: W7ASA on March 24, 2013, 07:22:28 PM
I have noticed that zero beating is hit-&-miss.  It may simply be that ops do not understand that simply tuning the receiver until the tone 'sounds good' to their ear is not the same as having stations on the same frequency.  Another factor is the RIT being ON while the ops is tuning in the other station.  Zero beat/match the other station first - THEN - use the RIT to your heart's content. I do that often in longer contacts to give my ear a new pitch to listen to, but not change my transmit frequency.  Infact, one zero beat is achieved, I usually hit the dial lock - to prevent an 'ooops!' and use the RIT for subtle pitch changes, without changing the actual operating frequency. A few Hz - even 50 Hz is fine, but I've heard a spread that - like the posting station pointed-out - are outside a moderate bassband of 500Hz filter.

Personally. I'd rather go back to seperate receiver/transmitter for CW, but transceivers are very handy.


Spark Forever!
   ;^)


de Ray
W7asa ..._ ._


Title: RE: Does anybody zero beat a QSO anymore?
Post by: AK4YH on March 24, 2013, 08:08:40 PM
On my KX3 I can just hit the spot button, or look at the display and see where the other station is. My K1 needs to warm up a few minutes before being stable, so if I start a QSO right away, it tends to drift. My Rock-Mites, well, I can hear someone in the next band over, so.. ;-) RIT is a bit weird to me. I do understand how it works, but haven't found it useful yet. Actually, I have never used it.. I think I can get close enough by ear with my K1. Often, both stations probably expect the other guy to zero-beat..

Gil.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: VK5DO on March 25, 2013, 03:46:00 AM
I always zero beat.  My TS590 does it automatically with the touch of a button.  The ones that annoy me are when you get someone answer you off frequency, so while they're answering I zero beat to them and then after the next over they've tuned off again to maintain whatever they reckon zero beat is.  Luckily the TS590 zero beats the RIT as well.

Yours,

Dene
VK5DO
Vk4TN

 


Title: RE: Does anybody zero beat a QSO anymore?
Post by: AC2EU on March 25, 2013, 07:15:28 AM
I always zero beat.  My TS590 does it automatically with the touch of a button.  The ones that annoy me are when you get someone answer you off frequency, so while they're answering I zero beat to them and then after the next over they've tuned off again to maintain whatever they reckon zero beat is.  Luckily the TS590 zero beats the RIT as well.

Yours,

Dene
VK5DO
Vk4TN

 

Now that's what I call frustrating!  :o  That's like a HF cat and mouse game!

Not that I'm some world class op, but this thread has inspired me to do a club presentation about this stuff.
Apparently there are many HAMS that don't know how the whole tone vs zero beat concept works.
I liked the RIT tip for when 700hz gets monotonous. Works like a champ.  ;D


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K0OD on March 25, 2013, 08:48:07 AM
Jim, where are you hearing all this off-frequency CW?

You say you're new to CW and not fast. I don't hear a problem while chasing DX or contesting at 30+ wpm usually at the bottom of bands. Most off-frequency CW ops know what they're doing.

QRP or boat anchor operation, usually done higher in bands, is a special case, with worse VFOs or crystal controlled transmitters loosely grouped around standard frequencies.

Also, does anybody remember decades ago when League handbooks said it was bad form to call a DX station on his frequency?



Title: RE: Does anybody zero beat a QSO anymore?
Post by: AC2EU on March 25, 2013, 09:13:19 AM
Jim, where are you hearing all this off-frequency CW?

You say you're new to CW and not fast. I don't hear a problem while chasing DX or contesting at 30+ wpm usually at the bottom of bands. Most off-frequency CW ops know what they're doing.

QRP or boat anchor operation, usually done higher in bands, is a special case, with worse VFOs or crystal controlled transmitters loosely grouped around standard frequencies.

Also, does anybody remember decades ago when League handbooks said it was bad form to call a DX station on his frequency?



30+ wpm is out of my league. I tune by those guys.
I listen on 20, 30, 40, 80, and sometimes 160, depending where the activity is. I look for 10 to 20 wpm.
The problem is pervasive on all of those bands on maybe 30% of the QSOs.
The QSOs are NOT DX nor are they QRP.
Now I believe it is OK to ZB a DX station unless  a) he specifies "up" or B) it's obvious that the pileup is established "up".
At least that seems to be the practice... tell me if I'm wrong. I'm not doing cw dx at this stage.
The other phenomena is that cw ops are all over the place, up , down and in-between during "the chase". I don't know how one would figure out how to find the station in that mess without a "dx cluster" spotter!

There are lots of QRP rigs available ( I have a FT817). QRP itself is no excuse for bad drifting or "un-tuneable" equipment!
QRP itself is challenging enough without adding to the difficulties, right?  ;D


Title: RE: Does anybody zero beat a QSO anymore?
Post by: W9TM on March 26, 2013, 01:40:33 AM
As a fledgling CW Op, I spend a lot of time attempting to copy live QSOs as practice.
My receiver BW is about 500Hz in CW. Even so, some operators are so far off that I have to re-tune to hear the responding station who may be on the top or bottom edge ( or beyond) the BW!
What's up with that? BTW, I'm not talking about splits here, just a normal QSO.

Is it considered impolite to ask the responding station to zero beat your frequency? The ops I've heard just seem to ignore it.

In the evolution from separate tx and rx setups to transceivers, the issue of two stations transmitting cw on the same frequency has been an issue.  Some early transceivers such as the KWM-2 or SB101 had neither RIT or an adjustable cw offset freq.  If you tuned in a sig to a reasonable pitch to listen to, you were off freq (to the other station) when you transmitted.  He'd retune a bit to hear you and then would be off freq (to you) when he transmitted.  So the two would go leap frogging down the band.  Various schemes have been incorporated over the years, but many popular transceivers still on the air are SSB orientated with CW as a second thought and are not convenient or easy to ensure you're on freq when you call.






Title: RE: Does anybody zero beat a QSO anymore?
Post by: N4OI on March 26, 2013, 04:50:27 AM
As a fledgling CW Op, I spend a lot of time attempting to copy live QSOs as practice.
My receiver BW is about 500Hz in CW. Even so, some operators are so far off that I have to re-tune to hear the responding station who may be on the top or bottom edge ( or beyond) the BW!
What's up with that? BTW, I'm not talking about splits here, just a normal QSO.

Is it considered impolite to ask the responding station to zero beat your frequency? The ops I've heard just seem to ignore it.

Yes, 500Hz is a bit much, but generally it is my job to accommodate the op who is returning my CQ.  I will leave my bandwidth wide while listening and then use my RIT and filters to make copy as easy as I need.  I would never even consider asking someone who just paid me the compliment of replying to my CQ to change his transmit frequency so I will not need to do any work!

And although zero beating is the topic here, the same concept could be applied to my caller's buggy fist, use of QRP, or abbreviations.  It would be rude for me to ask the caller to switch to a keyer, increase power, or spell out their words!  In a fishing analogy, would I get upset when a five-pound bass hits my crankbait on the other side of a stump?  No -- the fun is in the challenge!

73 ES GOD BLESS U ES URS DE KEN N4OI   ;D

 



Title: RE: Does anybody zero beat a QSO anymore?
Post by: N3QE on March 26, 2013, 06:26:10 AM
For a conversational QSO, insisting on zero-beat is IMHO unreasonable. Your filter choice (500 Hz) is surprisingly narrow for non-crowded conditions, and you do have a RIT knob you know. Historically, conversational CW QSO's with simple novice-type equipment allowed for offsets of many kHz as "normal", and of course splits of several kHz are perfectly natural with much CW DX work.

I know there are guys out there who insist on zero-beating because they use super narrow filters (e.g. one guy who posts here frequently seems to regard 50 Hz filter as "Wide"!!!) but this is simply not reasonable to insist on, in non-crowded conditions.

Zero-beating the caller will often to be to your disadvantage with DX ("who is this guy UP who keeps calling?") or contests (where you want to differentiate yourself from the cluster-clickers.)


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KE7WAV on March 26, 2013, 09:47:19 PM
Trying to zero beat with some of my QRP rigs and my bad ears can be very difficult but I try to get as close as I can.  With a newer rig its a lot easier, but many of my old rigs and QRP rigs it can sure get tough to get within 100-200 hz of zero beat.  My hearing is bad enough sometimes I get my tablet out and use a chromatic tuner app to help me line up a little better.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: W7ASA on March 27, 2013, 12:02:12 PM
The refferences to the Novice requirement for crystal control are nostalgic for me - yes, but, have little to do with the equipment one 99% of contacts today being significantly off frequency.  I love boatanchors - really.  IT's also true that the  QSOs in the Novice bands in 1970's and before were usually on split tx/rx frequencies.  That was entirely because of crystal controlled transmitters being required for the Novice operator, just like the 75 Watt INput and 25Kc band slices were a requirement. The idea was to prevent Novices from being out of band during a day and age when equipment - especially home brewed equipment was not at ALL like the extremely accurate digital frequency controls that we have now.  In short - the long extinct Novice license rules have nothing to do with poor operating practice today. A little more learning and practice to improve skills is always a good thing.

There's some slack in zero beating - sure, old style rigs might be a little off & have more warm-up & drift & etc. and nobody is justified in being cranky over a few dozen Hz here or there, but when I receive an answer half a Kc away, by an op using a 'new' rig that cost more than three of my house payments, it's not likely a hardware problem - it's basically a 'training issue' as we used to say. So let's address that 'training'. As hams we're always learning something new, whether it's a new mode, antenna modifications or how to turn perfectly good  electrons into SMOKE!   :o  when there's a home brew or repair Ooops.

The passing the ham test is exciting and something to be applauded.  It is also the entry to ham radio. Learning to operate well especially in CW, requires more time more study of operational techniques and hopefully tutelage from a skilled operator. There's no reason to not try to improve.  Infact, it's actually enjoyable to become better with our radio skills. 

YMMV -


73 de Ray
W7ASA ..._ ._
ex - WN6WBP



Title: RE: Does anybody zero beat a QSO anymore?
Post by: N4OI on March 28, 2013, 03:56:37 AM
The refferences to the Novice requirement for crystal control are nostalgic for me - yes, but, have little to do with the equipment one 99% of contacts today being significantly off frequency.  .... 

And not just Novice equipment -- some of my QRP radios, such as the Rockmite transceiver and the Hendricks TwoFer transmitter, are rock-bound or just allow a slight frequency movement.  Regardless, I will point my half watt to any CQs I can hear in my very wide passband!  Amazingly, a lot of folks find me for a solid QRP QSO.

73 ES GOD BLESS U ES URS DE KEN N4OI   ;D


Title: RE: Does anybody zero beat a QSO anymore?
Post by: W7ASA on March 28, 2013, 06:36:09 AM
I Love my RockMite too!  The receiver is rockbound with the slight off-set as well as the TX, though.  What this other fellow was reffering to was back in our Novice days, you would only have a couple of crystals ("Rocks") and so after calling CQ, we would tune up/down the Nocive band searching for stations responding to your call: not an easy task with a beginner's code speed of  5 words per minute!  ha ha

That RockMite really is amazing though. I regularly enjoy ragchews at 800-1000 miles with it's 'mighty' half Watt. The receiver -as you pointed out- is wide open, but very sensitive. The best filter is still between the operator's ears.


73 de Ray
W7ASA ..._ ._


Title: RE: Does anybody zero beat a QSO anymore?
Post by: HAMNCHEESE on March 30, 2013, 08:11:54 AM
I can't believe how incredibly lazy hams have become.

I, myself, have struggled with myopic hams who demand calling them ON and ONLY ON their frequency. There have even been some who advised me I was "off frequency." Off frequency? What is this, a channel? There is no such thing as "off frequency" iin amateur radio unless you are out of band.

Years ago, before they created give-away licenses, hams called CQ and then would tune up and down ACROSS their transmit frequency. It was just good operating practice. Now apparently we have morphed into a group that would better be suited to CB.

Tuning 10 kHz up and down on each side of a transmit frequency is evidently more energy than some wish to expend to participate in the art of radiocommunication. I must concede that those operators have already endured the rigors of plugging in their rig and turning it on.

I wish we could get back to real radio operators and not those who wish to operate their equipment like a vending machine.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K0OD on March 30, 2013, 09:05:50 AM
Quote
There is no such thing as "off frequency" iin amateur radio unless you are out of band.

Actually there is. On 60 meters. Or on some digital modes. You don't want to be off the calling frequency on VHF/UHF when looking for weak signal DX. Meteor bursts. 

Not every radio has an RIT or two VFOs. Some RITs have limited range.

Responding off frequency may indicate an alignment or drift problem that should be corrected. Often it simply means an RIT was left on.

If you call a station on CW or digital more than a few hundred Hz off, you may not be heard. I usually use a brick wall 200 Hz filter in contests. Sometimes 100 Hz or even less.

It's about context. Being way off is acceptable in the QRP or boat anchor "windows."


Title: RE: Does anybody zero beat a QSO anymore?
Post by: AC2EU on March 30, 2013, 09:48:50 AM
I can't believe how incredibly lazy hams have become.

I, myself, have struggled with myopic hams who demand calling them ON and ONLY ON their frequency. There have even been some who advised me I was "off frequency." Off frequency? What is this, a channel? There is no such thing as "off frequency" iin amateur radio unless you are out of band.

Years ago, before they created give-away licenses, hams called CQ and then would tune up and down ACROSS their transmit frequency. It was just good operating practice. Now apparently we have morphed into a group that would better be suited to CB.

Tuning 10 kHz up and down on each side of a transmit frequency is evidently more energy than some wish to expend to participate in the art of radiocommunication. I must concede that those operators have already endured the rigors of plugging in their rig and turning it on.

I wish we could get back to real radio operators and not those who wish to operate their equipment like a vending machine.

Well Hamncheese,
I guess I would respect your point of view more if you used your call sign. Do you have a call sign?

Anyway, rigs have progressed a long way since the spark gap transmitter and coherer that you were using. In case you are unaware, they are now illegal to use due to "RF pollution".
So far, I haven't seen anyone here ( except you!) indicate that a 20KHZ BW is a reasonable target area when responding to a calling station. The consensus seems to be 2.5Khz BW is more than enough... and it is!

Yeah, I may be an "EXTRA lite", warmed over CBer or whatever you choose to call guys who haven't been HAMs for more than 50 years, but I DO know how to operate my radio in numerous modes. I even home brew some of it. Imagine that!   :o

I started this post to better understand the art of CW and why some folks zero beat, some miss by 150HZ or so, others are way off. ( again, I'm not talking about splits).

It's not so much a matter of laziness, but if the calling station is using 500HZ, 1000HZ or 2.5KHZ filters, and you don't try to at least get close to the frequency, you may not be heard. Who's being lazy? The calling frequency picked the frequency, so why  not use a little skill to "find it" before responding? Besides, why use more BW for the QSO than you have to?

After reading the responses (thanks all!),there seems to be two schools of thought on this subject. Those who ZB and those who let the calling station "chase" them with the RIT. Bottom line, I gather that both are acceptable practice when the bands aren't crowed...  ???








Title: RE: Does anybody zero beat a QSO anymore?
Post by: ZENKI on March 31, 2013, 04:04:19 PM
Yeah I just dont get it either. I hear people call who can be us much as 800hz off zerobeat. When I hear their equipment they using modernn radios with the ability to easy zerobeat or automatically zerobeat.
There must be some misunderstanding of how to zerobeat a signal and have a CW QSO. Sometimes I suspect its someone using digital programs that are using audio generated CW and they working CW on SSB.

The best CW operators for zerobeat are homebrew QRP radio types, they know how to do it and are always spot on.  Why guys with modern radios cant do this is also beyond belief.
A lot of JA stations on 7mhz also seems to be off zerobeat, I dont know if they doing this because of QRM and birdies or what.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K1DA on April 01, 2013, 08:23:55 AM
The old "C" Line has a nice zero feature.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KF7DS on April 01, 2013, 09:49:44 PM
Not only is 0 beating good practice, you also get the most out of your filters. It is a necessity in close-in quarters in contesting.

Don KF7DS


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K9ZMD on April 01, 2013, 11:54:13 PM
Granted, there are circumstances when an op replying to a CQ cannot tune his TX frequency to match the CQing station (equipment limitations).  There are also circumstances where Zero Beating is a poor operating practice (for example, ZB on a DX station who is "listening up"), or frustratingly ineffective (multiple ZB replies to a CQ will QRM one another).  However, under normal circumstances, if station equipment is capable of tuning to a CQ frequency, then it is poor practice to haphazardly answer 500 Hz or more off the CQ frequency.  If the op knows how to ZB, but doesn't do it, then that's where laziness is the proper appellation.  If the op doesn't know how to ZB (or even understand the need), then that's the time for some Elmering to be applied.

Write this down: The CQing station sets the QSO frequency and should normally never change TX frequency to match a reply.  That is the convention, and doing it any other way often leads to rudely chaotic hopscotching around the band.  I'll acknowledge making one exception; namely, if I learn a replying station is rock bound, then I will move to his frequency.  Keep reading to learn the practical reasons to do so.

Under good band conditions, if a station replies within 100 Hz of my CQ, I'll always hear the signal and work the op.  No big deal.  RIT is a valuable aid to me under those circumstances, and both halves of the QSO are generally close enough to keep that little patch of spectrum clear of QRM. 

I also hear & answer stations that reply 500 or so Hz from my CQ, but that proves to be dicey on some bands.  Stations local to the other op may hear his frequency as a clear spot and jump on it.  Even if they first send QRL?, my quick QRL or C is so far off frequency that it is likely to be ignored, if even heard.  The ensuing "doubling" results in difficult copy for me.  Same for stations local to me; they may only hear my frequency as an invitingly quiet spot for their own CQ, so the op I'm trying to work is suffering QRM.  All could have been avoided if the replying op had only made a little effort to move his TX frequency somewhere near to my CQ.   Personally, I'd be ashamed if I couldn't get within 50 Hz of a CQ in less than two seconds, just by ear. (Actually, a station with CAT control & some sort of spectrum display - even as simple as HRD or MixW - can perfectly ZB a CQ in less than one second with just one mouse click.)

I have also heard and answered replies to my CQ that were over 900 Hz off my frequency (yes, I keep the band pass open while CQing).  If I then learn that the other op has a modern rig, my request for that station to tune to my signal is very reasonable.  Let's avoid the potential for QRM from another op who can't hear either of us, and let's leave one of those two widely separated frequencies free for someone else to use.



Title: RE: Does anybody zero beat a QSO anymore?
Post by: WB6DGN on April 02, 2013, 08:38:03 PM
Good Grief!  You can tell you're getting old when your complaints refer to, not how fast another op sends CW but, instead, how fast he SPEAKS!
Really sad thing about this; I'm serious!


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KD8IIC on April 03, 2013, 01:11:13 AM
Just sounds to me like you are not quite used to what your 500hz CW filtering does OM.Turn off the filter, zero beat the other guy, turn that 500hz filter bk on. I use my RIT on the transceiver but it's easier to use a seperate receiver to do the real work. 73.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: WD8DKB on January 14, 2014, 04:06:11 PM
On my IC-7200, there is no zero beat feature. I tune to match my sidetone . Or switch in the really narrow filter and tune for maximum signal strength. Another 7200 owner said to switch to SSB and zero beat the received cw signal, then switch back to CW mode. That seems to work well for me. Whether these ideas work on other rigs , I have no idea. Hopefully, I'm zeroing signals correctly at my end. Feel free to correct me if I'm not. Never too late to learn !  Max   


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KE6EE on January 15, 2014, 10:43:41 AM
On my IC-7200, there is no zero beat feature. I tune to match my sidetone . Or switch in the really narrow filter and tune for maximum signal strength. Another 7200 owner said to switch to SSB and zero beat the received cw signal, then switch back to CW mode. That seems to work well for me. Whether these ideas work on other rigs , I have no idea. Hopefully, I'm zeroing signals correctly at my end. Feel free to correct me if I'm not. Never too late to learn !  Max   

Matching the sidetone works (be sure to be on the correct side of zero beat depending on your bfo setup) and that's the way I usually do it. Switching to USB or LSB and tuning to zero beat also works on my rigs (new method for me). Max signal strength is also appropriate, but probably not as accurate as zero beat or matched sidetone methods.

In the old boat anchor days, zero beating was a more direct experiential process because most receivers had a bfo frequency knob on the front panel. You could tune for zero beat and then adjust the bfo frequency knob to either side of zero beat for whatever sidetone frequency you wanted. At zero beat you would also see your S meter peak (again not necessarily a very sharp indication, depending on signal strength and selectivity).

I think the rigs of more recent decades with their pre-set bfo frequencies have both simplified receiver tuning and also kept ops from experiencing what true zero beat is. Thus so many QSOs which are not really on the same frequency.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K4KRW on January 23, 2014, 02:34:24 PM
My 897D has a zero beat indicator that works great.  I have small QRP rigs built from kits.  I wanted the same functionality on those rigs as zero beating by ear was not at all easy. 

I found this:
http://www.wb3aal.com/Pages/K6XX/K6XXCWIndicatorKit.htm

My 2 Wilderness Radio Sierras and my OHR-100A all have one now.  If the rig is properly aligned and this add on correctly installed and configured it works wonderfully.  If you see the light flashing in time with the signal, you are zero beat. 

The instructions are pretty generic.  So, you have to figure out where to tap in for power and for the audio sample.  But, I managed it on two different type rigs without too much difficulty.

I had to buy a bezel for the LED.  Other than that, the kit had everything.

Richard - K4KRW


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K8AXW on January 24, 2014, 09:02:25 AM
ASA:  Ray, I'm directing my question to you because I seem to understand your explanations better than most of the others.

It seems that I have been operating CW incorrectly for 57 years or I simply don't know what the hell everyone is talking about with this "zero beating."

My procedure when operating CW is to tune a CW station until it gives me a nice 800Hz tone...and call him.  This seems to work OK and I've never had someone tell me that I was off frequency. 

To me "zero beating" is to tune the received CW signal down to a null which then means I don't hear anything.  Now if my radio has RIT, I of course can bring him up out of the null to a good sounding audio signal. 

However, if my radio doesn't have RIT then how does one properly tune a CW signal?

Ray, I'm sure you've seen confused old people or old people easily confused...... well this is where I am.  All at once I don't understand this simple process, a process that I've use for 57 years as I mentioned. 

I don't know rather to feel that I simply don't understand what is being discussed here or feel like an ass for not using proper procedure for all these years!

Can you simplify this for me?  Anyone?

Al - K8AXW


Title: RE: Does anybody zero beat a QSO anymore?
Post by: AA4PB on January 24, 2014, 09:21:25 AM
In this case, "zero beating" means tuning your transceiver until your transmit frequency is exactly the same (i.e. zero beat) as the other station's transmit frequency. That's done by tuning the signal until the beat note is equal to the transceiver's frequency offset (800Hz in your case). The exact frequency is different for different transceivers.

The "beat detector" that was mentioned is a tuning aid with an LED that lights when the received audio note is equal to whatever frequency the detector is set to. In most cases these use a phase locked loop (PLL) that is adjusted to the same frequency as your transceiver's offset. Then you get a visual indication when the tuning is correct in lieu of requiring you to have a perfect pitch ear.



Title: RE: Does anybody zero beat a QSO anymore?
Post by: K8AXW on January 24, 2014, 09:51:46 AM
PB: I understand your explanation to mean that I've been doing it properly and the whole discussion here has been over 100-200Hz because of differences in hearing?



Title: RE: Does anybody zero beat a QSO anymore?
Post by: AA4PB on January 24, 2014, 10:00:05 AM
PB: I understand your explanation to mean that I've been doing it properly and the whole discussion here has been over 100-200Hz because of differences in hearing?

You are doing it correctly. The only time it should become a problem is if the other station is using a very narrow filter and your tuning error results in you being outside the bandwidth of his receiver so that he doesn't hear you.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: PA0KDW on January 24, 2014, 12:28:14 PM
There is another point here, may be it is already mentioned, Most of the text I let pronounce due to visually impaired.

I am used to homebrew my own equipment.

For CW a direct conversion receiver and transmitter is OK.  However you have your sharp CW filtering in the audio, say at 800 Hz center frequency.
That means that you get two points of reception on your frequency scale with 800 Hz beatnote left and right of the transmitting frequency of the received station. So when you transmit you need an offset that is the same (800 Hz), however it must be on the same side of the transmitting station. So in one of your two receiving points you have a severe tx offset of the received station.

Frans


Title: RE: Does anybody zero beat a QSO anymore?
Post by: K8AXW on January 24, 2014, 05:45:19 PM
Frans:  You are 100% correct.  I built a direct conversion 40m CW transceiver many years ago (I still have it) and one of the first things I had to focus on was using the correct side-band.

I haven't used this rig for many years but as I recall there was a protocol on which side-band to use for the various bands, exactly like the existing SSB protocol.

You've made a good point.  I have been having a very difficult time understanding what has been discussed here.

Al - K8AXW


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KE7TMA on January 28, 2014, 05:32:23 PM
If the other guy isn't within my 500Hz passband he isn't answering my CQ.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KI6LZ on January 28, 2014, 06:10:49 PM
Gave up zero beating years ago. Would suggest the same to all. After a CQ everyone zero beat to me and I could not copy anyone. Now I offset my xmit freq abt 30-100 Hz and seem to get through to CQers easily.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KE7TMA on January 31, 2014, 03:03:26 PM
Gave up zero beating years ago. Would suggest the same to all. After a CQ everyone zero beat to me and I could not copy anyone. Now I offset my xmit freq abt 30-100 Hz and seem to get through to CQers easily.


Isn't this more of a sign that your transceiver's indicated and actual frequencies are out of calibration than anything else?


Title: RE: Does anybody zero beat a QSO anymore?
Post by: WA9CFK on February 03, 2014, 10:53:44 AM
If two stations were at true zero beat they would not hear each other. Most modern transceivers offset the transmitted signal a small amount.

When using a separate transmitter and receiver I set my transmitted frequency a tad above true zero beat. This is particularly true with direct conversion receivers which tune both sides of zero beat.



Title: RE: Does anybody zero beat a QSO anymore?
Post by: AA4PB on February 03, 2014, 11:03:11 AM
If your transmit frequencies are zero beat (i.e. identical) then you will hear each other. You won't hear him if you set your receiver zero beat to his transmitter.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: WA9CFK on February 06, 2014, 02:37:06 PM
With a modern transceiver you tune in the signal in until it sounds good, transmit, and the rig has taken care of the frequency offset etc.

When I play with my 1960's vintage receiver, I can tune above and below the zero beat note and listen; so where do I set my transmitter?
 
My experience is to tune the receiver through zero beat on the received signal, to a pleasant sounding note on the low frequency side of zero beat.

Then I listen to my transmitter signal as it passes through the low side frequency zero beat to the same note on the high frequency side.
 
This offsets the transmitter frequency up the same amount as the lower offset I selected for the receiver or the same as the received frequency.

Try not to think too hard on this or like me you will be mumbling to yourself.   :o    It was a lot easier as a rock-bound novice when you transmitted then scanned the band or a reply.  ;)
   


Title: RE: Does anybody zero beat a QSO anymore?
Post by: W1JKA on February 07, 2014, 03:45:36 AM
Re: WA9CFK  reply #40

You nailed it, it's called the KISS principle.

Your two answers concerning modern vs. vintage gear should be added to the multiple guess question pool for the Extra Class learners permit issued by the FCC.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: KF4ZGZ on February 08, 2014, 10:37:36 AM
Not many.
And I ,for one, am glad. It allows me to take a few seconds, zero beat, and bust a cw pile-up with one call on 100 watts and a crappy antenna.
SHHHHHH!

It can be out little secret!

Matt


Title: RE: Does anybody zero beat a QSO anymore?
Post by: AA4PB on February 08, 2014, 11:05:58 AM
With a modern transceiver you tune in the signal in until it sounds good, transmit, and the rig has taken care of the frequency offset etc.

If you want to be exactly on the other station's frequency (zero beat) then you have to tune the transceiver until the tone of the CW signal exactly matches your Rx/Tx offset. That is normally equal to your sidetone frequency if the transceiver is properly aligned. If you are using a wide filter and you just tune to some tone frequency that sounds good to you, you may be off frequency by several hundred Hz. If the other station is using a narrow filter he may not hear you at all if you are that far off.



Title: RE: Does anybody zero beat a QSO anymore?
Post by: KI6LZ on February 08, 2014, 11:17:10 AM
Here's one instance where you don't want to zero beat. During a contest, think it was sweepstakes, after calling CQ I had at least 5 stations calling me. For some reason 4 were zero beat, nearly same signal strength. The 1 that was off by 80 HZ I could copy, those zero beat I could not make out any letters of their call sign. As mentioned earlier I always have a shift somewhere between 30 and 100 HZ to avoid those that zero beat. I always seem to get through. Tip of the day.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: N3QE on February 14, 2014, 06:27:30 AM
Gave up zero beating years ago. Would suggest the same to all. After a CQ everyone zero beat to me and I could not copy anyone. Now I offset my xmit freq abt 30-100 Hz and seem to get through to CQers easily.


Isn't this more of a sign that your transceiver's indicated and actual frequencies are out of calibration than anything else?

No. What KI6LZ is talking about, is a dozen people clicking on a packet spot. 11 go to the "exact right frequency of the spot" and end up clobbering each other in a big mess. One goes offset by a hundred Hz or so and stands out from everyone else and gets the QSO easy.

I feel that in addition to packet spots, another factor making things worse is the built in rig tools that make it easy to visually zero beat a station within a few Hz.

I myself would advocate random offsets of up to a few hundred Hz as most effective.

Tim.


Title: RE: Does anybody zero beat a QSO anymore?
Post by: N4OI on February 14, 2014, 06:51:41 AM

For simplex DX pileups, I appreciate when the responders move a couple dozen cycles or so off the DX caller's frequency.  The tone difference helps to discern the caller from the responders....   I assume the DX caller will have his filter opened a bit to hear everyone....

For rag chews it really does not matter, IMO...  ("Zero beat" is kind of temporary anyway with my old TenTec Century 21  ;D)

73


Title: RE: Does anybody zero beat a QSO anymore?
Post by: WB5JWI on March 05, 2014, 09:35:40 AM
A couple of things. My old TS-520 had a 600 Hz offset on Transmit. I set the RIT down 600, tuned to null the signal, turned off the RIT and I was there. My new TS-480 has an 800 Hz offset. I could use the same method but I don't usually bother. For one, there is a button to zero beat but I don't use it mostly. I used the same trick to stay inside the band edge when down low. With the accurate read out on the TS-480 it is much less of a concern but I still have to stay 800 Hz above the bottom of the band.

The question is why zero beat so examine it. When my boat anchor is in use, I am rock bound so I still do a little hunting with the receiver. When on a more modern rig, I keep the filters at 1000 Hz when calling and only cut down when I've gotten close. If I'm called off frequency, I use the RIT and then filter. CW is a narrow mode around 250 Hz in width. So, if we are using 500 Hz filters, you can be off frequency by 200 Hz and who cares?

I tune close, not everyone opens up their filters when calling CQ but I just don't see the point of getting "anal retentive" about spot on zero beating. I'm told it is good operating practice but I don't see the merit in missing the fun trying to get the last 10 Hz off set removed.

Just my not so humble opinion, of course.