I have a Baby Loop Antenna and am well satisfied with it. Because of CCRs all of my antennas are in the attic where the ability to rotate the Baby Loop really shines. My other antenna (a SteppIR Urban Beam) cannot be moved.
I am running a K-Line (K3s/P3/KPA500/KAT500) and, of late have mostly been on FT8 with WSJTX/JTAlertx software.
The rub is that I’ve got four devices connected via CAT to the radio (PC, P3, SteppIR and Baby Loop). The PC and P3 both require two-way communication to set and read the frequency. The two tunable antennas need to know the radio frequency. The SteppIR works just fine in listen only mode (RX and GND lines connected).
Unfortunately the Baby Loop is more problematic. As has been reported elsewhere here the ATU polls the radio roughly once per second and expects to have complete control. This creates a conflict when WSJTX running on the PC attempts to communicate with the radio with the result that PC rig control fails and the the Baby Loop does not track frequency.
While I very much like my Baby Loop a principal shortcoming is not in the device itself but the inability to readily communicate on technical issues with anyone in English. As a result, although C-M markets a serial switch, I have been unable to confirm that it will workin my application. Given its expense (USD 500 from DX Engineering) I decided to go in another direction rather than ordering one just to “give it a shot.”
The purpose of this post is to report entirely successful results using N6TV’s Serial Box (https://www.qrz.com/db/n6tv ). The Serial Box is a multi port breakout box jumper configurable for a host of applications. In my case it takes a DE9 “radio” feed from the P3 and provides connections to both the Baby Loop and the SteppIR as well as the PC USB port. Importantly it breaks out the Loop TXD signal which is not used to prevent conflicts with the PC and P3. When the PC polls the radio for frequency information both antennas now track. Frequency changes can be initiated via the tuning knob, P3 or PC. While I am not saying that similar results could not have been obtained (at more than twice the cost) using the C-M Serial Switch, what you cannot get is anything like the knowledge and customer service from Bob Wilson (N6TV). When I inquired about his products he sent me a series of detailed emails including suggested block diagrams. Before ordering Bob wanted to speak by telephone to make certain he fully understood my needs. After I purchased his Serial Box I had a number of issues all of which Bob patiently worked through with me. In total we’ve exchanged over two dozen emails. Getting my lashup to work properly required more than just knowledge about the N6TV Serial Box it required familiarity with the K3s/P3/PC cabling and correctly modifying the K3s and WSJTX settings. I can say with certainty that I would not have gotten it right without Bob’s help. I have no connection with Bob other than being a satisfied customer.