Author Topic: "Echo" in transmit audio when using Control at home  (Read 2087 times)

K7ZS

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Hello All

I use the RemoteRig system at my home QTH a lot, since the 'best' station is out in a remote ham shack.  I am having the recurring problem of an "ECHO" on my transmitted signal, due to the RF getting into the CONTROL unit.  I am running power, about 1 KW, but the antenna is 100 feet above ground, and the tower is over 100 feet from the room in the house.

If I use the tower situation right over the station (@ 75 feet) the problem becomes much worse.  This is not RF in the Shack, this is just the RR Control box injecting a delayed signal back into the audio.

Rig is a TS-480SAT, using the hand microphone.  RR Box is grounded, toroids on the power supply cable, but not on the others.  No other connections to the remote rig i.e. key paddle, noting in the I/O port or an external speaker.

I do NOT have this problem when using the radio directly to the amplifier, an Alpha 9500, so this is definitely a RR Control box issue in the near field of the transmit antenna.

Any suggestions???  I need this to work as I am having an electronic cardiac pacing device installed next week, and it has been suggested to keep my distance from the amplifier and antenna.

73 Kevin K7ZS


Any suggestions of whi

K7ZS

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Re: "Echo" in transmit audio when using Control at home
« Reply #1 on: 2014-07-29, 06:16:27 »
No responses REALLY? 

Nobody else has this problem?  To confirm this is not just a high power problem, I just went to 40 meters, even @ 100 watts with the 2 element Moxon Beam @ 85 feet overhead, with toroids on every cable (control, microphone, power, ethernet) and the RR box grounded, got HORRIBLE audio reports, both RF in the audio, and and a complete duplication of audio about 20-30 ms. later, creating the 'Echo' effect.

I have used this setup for a long time remotely, so it's not the long solved microphone ground lead swap in earlier radios.

There is no evidence of RF in the shack. (I have tried this in several places within the home, does not matter what room I am in)

I have a relatively early box, version 4, hardware version 5, serial number 2443, latest firmware, version 2.78.  This unit has the WIRELESS adapter too.

I would appreciate any insights here - hard to believe these boxes are that sensitive to RF.

Vy 73
Kevin K7ZS

K7ZS

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Re: "Echo" in transmit audio SOLVED
« Reply #2 on: 2014-08-06, 19:08:49 »
I have solved the echo problem I was having when operating my RemoteRig station on my LOCAL NETWORK.

In truth, there may be a technical solution, but I found a practical solution in the mean time.

This was a simple case of RFI getting into the audio stream via the MICROPHONE CORD!  The TS-480 hand microphone has about a 20" of the cable that is straight, and then the coiled cord segment.  Quite by accident, with stations listening to me to give me reports as I was putting more or less toroids on all the cables, said 'that was better', when in fact I had not done anything except stretch out the mic cable a bit.  As I would change the orientation, the RFI would increase or decrease.

SO, out with the BIG toroid (2.4" OD ring toroid in a 77 mix) I wrapped ALL of the 'straight' section of the mic cord through this large toroid (20 turns) and now it is BULLET PROOF.  I can run 1 KW+ on the 40 meter beam that is directly overhead and NO RFI.  Before the toroid, with only 20 watts on 40 meters on an antanna very distant the RFI was

I mention this, as the SAME RADIO of connected directly to the radio in the same position and running the same power is perfectly clean.

Perhaps the RR box has inadequate shielding of the audio circuit in the Control box?

The setup is now working great, and is a pleasure!

73 Kevin K7ZS

dj0qn

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Re: "Echo" in transmit audio when using Control at home
« Reply #3 on: 2014-08-07, 13:26:27 »
Perhaps you have the wrong microphone connection wired? See the manual page 177 for details.
This causes the setup to be very RF sensitive if you use the wrong one.

73,
Mitch DJ0QN / K7DX

OH6XE

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Re: "Echo" in transmit audio when using Control at home
« Reply #4 on: 2017-08-04, 09:04:32 »
I have same kind of problem includes
srange noise just push PTT. At  5 W kenwood ts 480
It is quite small when mic gain is zero but if you turn mic gain to 1 it starts and getting worse if add power.
Have anyone has this kind of problem

dj0qn

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Re: "Echo" in transmit audio when using Control at home
« Reply #5 on: 2017-08-04, 12:16:17 »
An echo is usually caused by the "monitor" function. When operating remote, one must always have
monitor turned off in SSB and CW modes completely, otherwise it will drive you crazy.

73,
Mitch DJ0QN / K7DX

OH6XE

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Re: "Echo" in transmit audio when using Control at home
« Reply #6 on: 2017-08-04, 17:00:26 »
If you mean ts480 mic sound monitor function its OFF.
Also strange is that ALC jumps top when mic gain is 50, when alc is reasonable value mic gain should be 10 or less?
« Last Edit: 2017-08-04, 17:18:12 by OH6XE »