WA9UDW - Proficio Transmit Anomalies - Receive is OK


Terry / WA9UDW
 
Edited

Operating System: Windows 7 Professional 32 bit - 1.6 GHz processor - 3 GB usable ram

Test Equipment: Brymen BM235 DMM; Tekronix 2465B 400 MHz Oscilloscope; Icom IC-7000 transceiver; Vectronics transmatch with 300 W dummy load; Radio Shack digital swr/power meter; 160-10 M antennas; AnaTek ESR capacitor meter; temperature gun; VTVM; VOM; skin; eyes; ears; nose.

DC Supply: 13.68 vdc standby / 13.52 vdc with full output on 160 M.

SDR Applications: MSCC; HDSDR; Genesis

I finally got around to assembly and operation of my Proficio in February. It seemed to be functioning ok where I used it...mostly on 17M and 20M CW with MSCC, driving a Hardrock-50 amplifier. (I also did some AM & SSB testing into a dummy load)
 
The first sign of something being amiss was with the key down, transmitting a carrier, there would be an occasional hick-up in the output. The carrier would drop for a fraction of second, maybe about two events per minute. I use the IC-7000 as a side-tone monitor. Days ahead, the next thing to happen was what sounded like a "hashy" oscillation of the output signal. Lowering the output level to about 1-2 W would stop the oscillation. Sometimes in this state, the transmitter would lock up, and I would have to switch off the power supply to disable it.  I ran it a few more days at reduced drive into the Hardrock-50, but eventually measurable output ceased on 17 & 15 M. But a weak signal can still be heard in the IC-7000. I looked at the output carrier wave forms, and found symmetry distortion on all bands, that is most noticeable on 40-10 M. Also there appears to be some "FM-ing" mostly centered around 40 M.

Upon examining the circuit board, I noticed bulging on the tops of L5, L6, L7, L10, L11 & L12.

The Proficio is being operated in open air, with the fan that comes with the panel kit, resting on top of the heat sink and wired for 12 vdc.

May I have possibly damaged the static sensitive PA MOSFET during assembly?

Suggestions?

Terry - WA9UDW


 

Hi Terry
 
That is the strangest fault I have ever come across!
 
Generally the PA is virtually indestructible. For  L5, L6, L7, L10, L11 & L12 to be damaged the current must have been very high.
 
I would check that U20 is actually switching the relays. U20 could be damaged or have a bad connection. I would also use a scope to check the input and output of the PA LPF's. To do this I would monitor the voltage at C61 and at the antenna into a dummy load.
 
Best of luck! An interesting problem
 
73
Richard
VK6FR
 
 
 
 
 
 
 

------ Original Message ------
From: "Terry / WA9UDW via groups.io" <wa9udwterry@...>
Sent: 25/03/2021 7:18:38 AM
Subject: [Multus SDR] WA9UDW - Proficio Transmit Anomalies - Receive is OK
 

[Edited Message Follows]

Operating System: Windows 7 Professional 32 bit - 1.6 GHz processor - 3 GB usable ram

Test Equipment: Brymen BM235 DMM; Tekronix 2465B 400 MHz Oscilloscope; Icom IC-7000 transceiver; Vectronics transmatch with 300 W dummy load; Radio Shack digital swr/power meter; 160-10 M antennas; AnaTek ESR capacitor meter; temperature gun; VTVM; VOM; skin; eyes; ears; nose.

DC Supply: 13.68 vdc standby / 13.52 vdc with full output on 160 M.

SDR Applications: MSCC; HDSDR; Genesis

I finally got around to assembly and operation of my Proficio in February. It seemed to be functioning ok where I used it...mostly on 17M and 20M CW with MSCC, driving a Hardrock-50 amplifier. (I also did some AM & SSB testing into a dummy load)
 
The first sign of something being amiss was with the key down, transmitting a carrier, there would be an occasional hick-up in the output. The carrier would drop for a fraction of second, maybe about two events per minute. I use the IC-7000 as a side-tone monitor. Days ahead, the next thing to happen was what sounded like a "hashy" oscillation of the output signal. Lowering the output level to about 1-2 W would stop the oscillation. Sometimes in this state, the transmitter would lock up, and I would have to switch off the power supply to disable it.  I ran it a few more days at reduced drive into the Hardrock-50, but eventually measurable output ceased on 17 & 15 M. But a weak signal can still be heard in the IC-7000. I looked at the output carrier wave forms, and found symmetry distortion on all bands, that is most noticeable on 40-10 M. Also there appears to be some "FM-ing" mostly centered around 40 M.

Upon examining the circuit board, I noticed bulging on the tops of L5, L6, L7, L10, L11 & L12.

The Proficio is being operated in open air, with the fan that comes with the panel kit, resting on top of the heat sink and wired for 12 vdc.

May I have possibly damaged the static sensitive PA MOSFET during assembly?

Suggestions?

Terry - WA9UDW

Virus-free. www.avast.com


Ron / W4MMP
 

Hi Terry,

I would like to inspect the rig.  Please return it to me for inspection and/or repair.   I will PM you with my shipping address.

73,
Ron / W4MMP
On 3/24/2021 19:18, Terry / WA9UDW via groups.io wrote:

[Edited Message Follows]

Operating System: Windows 7 Professional 32 bit - 1.6 GHz processor - 3 GB usable ram

Test Equipment: Brymen BM235 DMM; Tekronix 2465B 400 MHz Oscilloscope; Icom IC-7000 transceiver; Vectronics transmatch with 300 W dummy load; Radio Shack digital swr/power meter; 160-10 M antennas; AnaTek ESR capacitor meter; temperature gun; VTVM; VOM; skin; eyes; ears; nose.

DC Supply: 13.68 vdc standby / 13.52 vdc with full output on 160 M.

SDR Applications: MSCC; HDSDR; Genesis

I finally got around to assembly and operation of my Proficio in February. It seemed to be functioning ok where I used it...mostly on 17M and 20M CW with MSCC, driving a Hardrock-50 amplifier. (I also did some AM & SSB testing into a dummy load)
 
The first sign of something being amiss was with the key down, transmitting a carrier, there would be an occasional hick-up in the output. The carrier would drop for a fraction of second, maybe about two events per minute. I use the IC-7000 as a side-tone monitor. Days ahead, the next thing to happen was what sounded like a "hashy" oscillation of the output signal. Lowering the output level to about 1-2 W would stop the oscillation. Sometimes in this state, the transmitter would lock up, and I would have to switch off the power supply to disable it.  I ran it a few more days at reduced drive into the Hardrock-50, but eventually measurable output ceased on 17 & 15 M. But a weak signal can still be heard in the IC-7000. I looked at the output carrier wave forms, and found symmetry distortion on all bands, that is most noticeable on 40-10 M. Also there appears to be some "FM-ing" mostly centered around 40 M.

Upon examining the circuit board, I noticed bulging on the tops of L5, L6, L7, L10, L11 & L12.

The Proficio is being operated in open air, with the fan that comes with the panel kit, resting on top of the heat sink and wired for 12 vdc.

May I have possibly damaged the static sensitive PA MOSFET during assembly?

Suggestions?

Terry - WA9UDW

--
Thank you for your support and business,
73,
The Multus SDR,LLC Team,
Ron / W4MMP


Terry / WA9UDW
 

Thank you Richard and Ron!

Ron, I could mail the rig to you tomorrow, Friday, via USPS Priority mail. I don't yet know how to send and receive PMs on this site, but maybe it will become obvious when you send your shipping info.

73, Terry / WA9UDW


Ron / W4MMP
 

Hi Terry,
When using the groups.IO web interface,  click the reply button.  At the bottom right there is a "Private" button.  Click that and your reply will be send only to the person you are replying to.
--
Thank you for your support and business,
73,
The Multus SDR,LLC Team,
Ron / W4MMP