60m giving "Interlock is preventing transmission" error on AU-520M

GM7MTK

I'm on the air for the first day with my new AU-520M. When I try and transmit on 60m (5395kHz USB specifically) within one of the allowed UK 60m segments I get an Interlock is preventing transmission error. That part of the UK bandplan is from 5395 - 5401.5kHz.
I'm only using the radio, no external software control.
In Menu > Radio
HW Version = 4.2.20.41343
Region = GBR
In Menu > TX Band Settings no PTT Inhibits are selected and for 60m RF Pwr = 20 (we are limited to 100W on 60m in the UK)
The RF Pwr display below Menu in top centre of the screen remains greyed out as I tune through the 60m band. RF Pwr never shows in red.
Am I doing anything obviously wrong please?
Many thanks
Julian GM7MTK
ps I have a full UK licence so I am permitted to use 60m on that frequency (and my Yaesu FTDX101D works perfectly there)

Mike-VA3MW

@GM7MTK it might not be a TURF issue.

Every country on 60M is different but most users get caught with their Transmit Bandwidth being too wide.

Make sure you SSB TX Audio LPF is 3000hz or less, or, at least that would be the first thing I would check. Any wider and you may be transmitting out of band.

Other UK operators might help with exact settings.

Erik Carling EI4KF

I would not take it for granted that Region = GBR is the same as having a correct look up TURF file in the radio. Check this with your dealer. A recent radio from ML&S that I bought for my G0CGL station had a 60m no TX issue and they sent me a TURF same day that corrected the problem. I cannot remember if Region = GBR (I think it was) but I would still liaise with your dealer. If it was ML&S you'll get good service, if some other dealer you can always open a Help Desk ticket. Flex will sort it for you.

GM7MTK

Thanks Erik, it was ML&S I bought it from. I'll contact them on Monday and I'll also ask them what I do with a TURF file when I get it.
I presume if I want to take it on holiday to the USA at some point I'll need a different TURF file to operate 3.5-4 MHz, 7-7.3 MHz etc?

Erik Carling EI4KF

I am assuming it is a TURF file issue. But ML&S will know.

You have a good point. You would need a TURF for the region of operation when on 60m & 40m. But it is only a small file you save to your computer. In SmartSDR, select “Radio Setup”. Click on the “Radio” tab.
Locate the radio’s Region information line and click on the “Change” button.
When the file selection dialog box appears, select the TURF file sent to you for your
radio and then click the “Open” button.
When the modification of the radio’s transmit restriction is complete, a popup “bubble
message” will be displayed indicating if the radio was modified successfully.

Ahead of taking the radio to the USA, contact Flex Helpdesk and ask for a USA region TURF, explaining your circumstances. They are very helpful.

Gord-VA7GP

I requested a TURF for Canada (we have continuously-usable spectrum on 60m, in addition to channels).

I think it only took Tim about 1 day to respond to my Help Desk request. His reply, and the TURF file, were found in the HelpDesk conversation (ie didn't arrive by email).

As Erik says, actual installation took mere moments, and I verified the expected result.

Painless.

Martin_G4ENZ

The TURF file you need is GBR+. I originally had the GBR file and received GBR+ after logging an issue with the Flex helpdesk. Be aware though, even with the GBR+ TURF file, there is a bug that affects 60m operation. You cannot TX on any frequency below 5.300 MHz. This issue is currently with the "Sustaining Engineering Group" and has a reference of SMART-12876.

I hope they resolve it soon as our 60m CW centre of operation is now RX only.

73 Martin - G4ENZ

GM7MTK

Many thanks all, the problem was resolved by applying a new GBR+ TURF file from ML&S today. I will be testing on 60m later today but I can now tune there and the RF Pwr indicator is now red not gray. Thanks again