After having decent results testing my first HD Radio, I bought a JVC KT-HDP1 HD Radio receiver to test AM HD Radio. The performance was disappointing.
The connectors were unusual sizes, except for the headphone output. None of the connectors I found on Digikey fit.
The antenna out port is for retransmitting the received signal in analog FM on the frequency of your choice.
The unit pulls 0.3A at 12V, around 4W. The current draw is about the same regardless of whether the radio is tuned to an HD station and whether the re-transmit feature is enabled.
Inside the unit there is a user interface board and a receiver board. The receiver board has a metal can that appears to function as a shield and heatsink. The can is attached by screws, no solder. It gets hot to the touch after a few minutes. I suspect most of that heat comes from the TI DSP.
We soldered a two-meter wire to the RX antenna port. The radio picked up no stations on AM and only the analog portion of FM stations. The digital subcarrier is 20dB down from the the FM, so HD radio only works with strong stations.
We soldered another two-meter wire to the TX antenna port. A trace going to the TX port also goes to a matching network connected to a metal antenna, perhaps making the external TX antenna optional. With a wire on the TX port, the radio began receiving many more stations, including some HD signals. It’s unclear why a wire on the TX port improved receive reception. It was still nowhere near as good as the Insignia radio we tested first.
The user interface was very frustrating. I couldn’t find any way to go to a frequency other than searching. If the signal doesn’t exceed the fixed threshold when the radio gets to that frequency, it just passes by.
Surprisingly, the re-transmit feature worked well. The Insignia radio picked up the analog signal transmitted from the JVC radio from across the room.
I feel so disappointed in this radio because it should be good.
- It’s a rare receiver that supports AM HD.
- It has a real receive antenna port, not some crude piece of wire.
- The transmit feature allows you to use it anywhere there’s an FM receiver.
This could have been something you could use in a car, with a stereo, or with an antenna on the roof for DXing. This radio obviously isn’t even close to that caliber. Someone should design a nice high performance radio that does HD and is good enough for DXing. CCrane says the discontinued Sony HDRF1HD is the only thing that comes close, and then only for FM. If someone makes a product or a kit for a high-performance HD radio, I’ll be eager to try it.
