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extricate
13th Jan 2019, 15:04
Hi there,

Is there any documentation on the correct way to do a HF call to a ground station? Specifically, do you press the transmit button once before you transmit?

Thanks

sonicbum
13th Jan 2019, 15:56
Hi there,

Is there any documentation on the correct way to do a HF call to a ground station? Specifically, do you press the transmit button once before you transmit?

Thanks

Try this thread (https://www.pprune.org/archive/index.php/t-255491.html).

extricate
14th Jan 2019, 00:23
Thanks.

Why is there a need to press transmit once and then press one more time before transmitting? Is there a term for it?

Eric Janson
14th Jan 2019, 01:13
Anytime you select a new HF frequency you key the mic once to tune the antenna to the selected frequency.
You will hear a tone while this is taking place.
When the tone stops you can transmit.

double_barrel
14th Jan 2019, 01:13
Specifically, do you press the transmit button once before you transmit?

To amplify the thread linked to above on your specific question.

In ssb mode, pressing the ptt button alone does nothing. The idea is to put RF into the antenna tuner to force it to"tune up" for the frequency in use. Since there is no carrier in ssb mode, there is no RF output unless you add some audio modulation (traditionally you whistle into the mic) Or select AM, press the ptt button for a second or 2, then go back to ssb. Some radios have a "tune" button which does the same thing.

And definitely use a much slower and clearer technique than on VHF.

excrab
14th Jan 2019, 12:32
The commonest way to initiate an HF call seems to be something like this :

1. Call “ Mumbai Mumbai Mumbai Mumbai Mumbai “ this should be done loudly and for
long enough that it blots out any other transmissions which are being made.
2. Upon receiving no response consider the following options
a) continue calling “Mumbai Mumbai Mumbai etc “
b) try using satcom if they ever answer the phone
c) broadcast on VHF for anyone with CPDLC to relay for you
d) give up and make stupid noises on 121.5 instead

This may be a regional specific technique but could presumably be used elsewhere, substituting “Shamwick” for “Mumbai” would be an option, in which case instead of farm yard noises on guard you could discuss base ball scores ��

Golden Rivet
14th Jan 2019, 14:28
You should give your frequency and approx location. Most HF stations have large steerable yagis. It helps if they know where you are.

FE Hoppy
15th Jan 2019, 00:57
Take your headset off and shout at the side window.
Always found this to be as effective as keying the mic in the South Atlantic.

double_barrel
15th Jan 2019, 04:18
Take your headset off and shout at the side window.
Always found this to be as effective as keying the mic in the South Atlantic.

You guys may need some training in HF comms! Or give it up completely!

lurkio
15th Jan 2019, 08:43
Press the transmit key, tap the mic and say "is this thing on?"

Meikleour
15th Jan 2019, 11:26
One of the best HF "exchanges" I heard some years ago was when over Burma (Yangon) heading west. The protocol was to call Calcutta and copy Dhaka and Rangoon. Despite attempting to reply to us , Dhaka kept replying loud and clear over Calcutta's tranmissions. Finally Calcutta snapped and , leaving aside all protocol, shouted loudly "Dhaka Dhaka SHUT UP SHUT UP!!!" Said in a wonderfully clear Indian accent.

jimtx
15th Jan 2019, 15:17
If you have a long winded transmission or maybe using "words twice" it sucks to have your stuck mike protection cut you off. Need to re-key before the timeout.

TwinJock
21st Jan 2019, 06:14
The commonest way to initiate an HF call seems to be something like this :

1. Call “ Mumbai Mumbai Mumbai Mumbai Mumbai “ this should be done loudly and for
long enough that it blots out any other transmissions which are being made.
2. Upon receiving no response consider the following options
a) continue calling “Mumbai Mumbai Mumbai etc “
b) try using satcom if they ever answer the phone
c) broadcast on VHF for anyone with CPDLC to relay for you
d) give up and make stupid noises on 121.5 instead

This may be a regional specific technique but could presumably be used elsewhere, substituting “Shamwick” for “Mumbai” would be an option, in which case instead of farm yard noises on guard you could discuss base ball scores ��

Exactly.... 😁 😁

eckhard
21st Jan 2019, 09:20
And definitely use a much slower and clearer technique than on VHF.

Good advice! Also, consider using a higher pitch for your speech; it may carry better and improve audibility at the receiver’s end.

In ssb mode, pressing the ptt button alone does nothing. The idea is to put RF into the antenna tuner to force it to"tune up" for the frequency in use. Since there is no carrier in ssb mode, there is no RF output unless you add some audio modulation (traditionally you whistle into the mic) Or select AM, press the ptt button for a second or 2, then go back to ssb. Some radios have a "tune" button which does the same thing.

I never knew that! Very interesting.