artifact on TX
Posted: Wed Mar 15, 2023 3:30 pm
Hello everyone,
I have 7000 dle mkii that was delivered last July (i guess we are calling these the mkiii but mine is still branded mkii and has the first newest chipset, not the most recent).
I run all sorts of audio equipment with the anan and I'm fanatical about clean audio. I've always noticed a small artifact when you key down, on the pan adapter but it has never been audible or visible in the transmitted signal.
About a week ago, i noticed what looked to be a 60hz hum on my TX. It was audible and visible. I've never had this issue before and decided to rearrange the shack and made certain all electronics were on one dedicated circuit. That didn't help. Here's what i have found:
not a 60hz hum, artifact is present from 0-95hz.
artifact is there with 1 watt drive, 100 watt drive and while using an amplifier.
artifact is present in dummy load and antenna system
artifact is present with microphone and/or audio interface, rack, xair, connected.
artifact is present with vac and line in
artifact peaks at about -72db on the pan adapter
when i key down with the amp engaged and no audio source connected to the rig, the artifact drives my amp to over 1kw and then the output power dissipates from there.
If I change my low cut freq to 100hz in the tx bandwidth, it goes away completely. If I change it to 95hz or lower, it's present.
If i disengage the "mic" button next to the gain slider, it goes away (remember there is no audio source, this is not noise from the mic). If i engage the mic button with 1db of gain, it's present.
I'm sending the radio off for diagnostic and possible repair. Would love to know the communities' thoughts?
Doug
kb2uka
I have 7000 dle mkii that was delivered last July (i guess we are calling these the mkiii but mine is still branded mkii and has the first newest chipset, not the most recent).
I run all sorts of audio equipment with the anan and I'm fanatical about clean audio. I've always noticed a small artifact when you key down, on the pan adapter but it has never been audible or visible in the transmitted signal.
About a week ago, i noticed what looked to be a 60hz hum on my TX. It was audible and visible. I've never had this issue before and decided to rearrange the shack and made certain all electronics were on one dedicated circuit. That didn't help. Here's what i have found:
not a 60hz hum, artifact is present from 0-95hz.
artifact is there with 1 watt drive, 100 watt drive and while using an amplifier.
artifact is present in dummy load and antenna system
artifact is present with microphone and/or audio interface, rack, xair, connected.
artifact is present with vac and line in
artifact peaks at about -72db on the pan adapter
when i key down with the amp engaged and no audio source connected to the rig, the artifact drives my amp to over 1kw and then the output power dissipates from there.
If I change my low cut freq to 100hz in the tx bandwidth, it goes away completely. If I change it to 95hz or lower, it's present.
If i disengage the "mic" button next to the gain slider, it goes away (remember there is no audio source, this is not noise from the mic). If i engage the mic button with 1db of gain, it's present.
I'm sending the radio off for diagnostic and possible repair. Would love to know the communities' thoughts?
Doug
kb2uka