[afw7962]

I made a directional coupler with audio pass-through using toroidal chokes (found on computer motherboards and switching power supplies) and 3 100pF disc capacitors all available at Radio Shack (parts drawer). I butchered their stereo 1/8 inch walkman-style headphone Y adaptor to create an insertable passive RF coupler which will pass the stereo audio out of the radio without much alteration of the sound. The inductances are relatively high to keep annoying digital interference from other digital devices at bay as well since I use a USB line in streamer to record audio into my computer from the radio.

For the RF to go towards the audio-out/antenna-in of the Insignia the rF has to be choked off of the lines that form the existing audio connection which would short out the antenna signal coming from a real antenna. The chokes allow the audio to pass but NOT the RF signal which can be DIRECTED to the radio's antenna in. Obviously the audio and RF are multiplexed in the radio which expects you to be using a earphone as an antenna as well as a listening device. This coupler will split the signals so that you have RF-free audio that won't significantly affect the radio reception based on audio line position. The RF antenna signal will maintain ALL of its directional characteristics which will allow you to use the radio as a tuner and receive distant signals confidently. I'm using it to receive signals from Youngstown Ohio about 45 miles east of me with full HD recovery which could not happen with any length of wire antenna fashioned to pick up better. View the attached jpeg which has captions zoom in to read and view details. Everybody out there with REAL antennas can now use them with this very inexpensive radio.I DO suggest some type of antenna preamp that has at least 10dB gain to make up for insertion loss and some native impedance mismatching inherent with such a simple design. I'll make a video with audio examples in the very near future. The image must be a large file size for zooming into detail so I provided a link for that jpeg here:
http://drop.io/directionalcouplerfor...ss-through-jpg

 

[Vchat20]

Hehe. I was just listening to that same song on mine, same station when I was playing with mine earlier.

Could you possibly do up a quick and dirty mspaint diagram of how it's all wired up? I've been intending on trying to find a good way to integrate it into my car and it'd be nice to tie it into the vehicle's antenna. Your setup may just do that nicely.


Thankfully so far though just the tape adapter alone gets comparable reception to my skullcandy earbuds which is 10x better than alternatives such as feeding the audio into my laptop. And with the noise reduction turned off in the headunit, audio quality is great.


Truth be told compared to reviews of other HD radio units, the Insignia has good reception imho considering what it has to work with. And the analog reception is right up there with the original Walkman's. Just needs a bit of a boost on the HD side until stations start bumping up their transmit power.

 

[afw7962]

The 7 meg jpeg had to be linked and zoomed into for greater detail that 500K just wouldn't support. As I write this, I'm sending up a You Tube video which I will link to this thread which provides a better description and look at how this thing can work. It should be available in maybe 3 hours 2 of which it will take to upload to You tube itself.

 

[afw7962]

I'm confused by the inability to copy and paste my own video link without the embedded player option. I guess this is a new anti-copying deterrent.

Here is the link for the video that demonstrates this directional coupler

 

[Vchat20]

This should do the trick:

Took me a few tries. For reference the youtube tags here on AVS just want the video id's like:
Code:

[ YOUTUBEHD ] 9Oxp4o4bcck [ /YOUTUBEHD ]

 

[afw7962]

Thanks Vchat for helping me out with the You tube linking! I hope the video clarified enough of the design. I shot an email to the CMO of Best Buy and hopefully, this design suggestion can be turned into a sleek add-on accessory ( we can only hope!). At least the word has entered the corporate world of BB perhaps.

 

[afw7962]



Quote:
Originally Posted by afw7962 /forum/post/18181200


Thanks Vchat for helping me out with the You tube linking! I hope the video clarified enough of the design. I shot an email to the CMO of Best Buy and hopefully, this design suggestion can be turned into a sleek add-on accessory ( we can only hope!). At least the word has entered the corporate world of BB perhaps.

I may have ventured way too far up the Food Chain to expect a response from the Insignia project team. If anyone in this forum has an inside link to the design team over there please be my guest and share this concept!

 

[digitaldel]

Hi there,


Thanks for the post and the pictures. Interesting project, we love to see our customers extend the capabilities of our products. How many folks are interested in this solution?


Thanks!


Digitaldel

Insignia Products

 

[bigtomNJO]



Quote:
Originally Posted by digitaldel /forum/post/18213813


Hi there,


Thanks for the post and the pictures. Interesting project, we love to see our customers extend the capabilities of our products. How many folks are interested in this solution?


Thanks!


Digitaldel

Insignia Products

As a Insignia owner, I would buy one.

 

[Vchat20]

Indeed. As an owner myself and seeing mobile situations really show the weakness of this device, I'd kill for one. I just had a trek to Boardman (Ohio) today and had the Insignia tuned to all the cumulus stations and not until I was within a few miles of the transmitters would the signal become fairly reliable with few dropouts. Any farther out and I was out of luck. This is either with my headphones or the tape adapter. I am dying to be able to tie it into the vehicle's antenna or better yet the tv antenna on my house to greatly improve the reception.


It does seem though that until stations get around to increasing their Tx power, the current state of HD affairs makes it a pre-requisite that a GOOD antenna is used. I think this is evident with many of the existing HD tuners either being able to use a decent lengthed dipole, car antenna, or some other external antenna connection being available.


I actually saw an RCA brand tv/fm amplifier today for real cheap with a good 10-12db boost and was really tempted to pick it up for this.

 

[afw7962]

Wow Thanks for responding Digitaldel! Everyone loves this radio for what it can do, and I'm confident that I speak for many that a directional coupler solution would be adopted by many as a must have accessory as important as the radio itself. The same way everyone FLOCKED to get on board the "ipod Dock Express", a home/mobile solution could be employed that would greatly interest existing owners of the NS-HD01 and thrill new potential buyers that want great reception and sound at a low entry cost point. Get it to your design guys; maybe a T shaped profile, SMT inductors and caps and your choice of a supplied SMA adapter to female F adapter for connector compactness. That could serve the "Home Tuner" solution. perhaps an additional "mobile solution" accessory would also include a dedicated 12volt active 10dB RF preamp that allows a Hi-pass FM VHF tap into a directly-coupled male/female Motorola-styled coupler hookup that allows existing direct connection to the vehicle antenna for AM/FM existing car radio hook-ups and allows a swing-out boosted RF line for the Insignia while the opposite "audio out" port replicates the existing 1/8 inch stereo phone jack that can be coupled into the Aux-in jacks common to many car stereos these days. It's all about MARKETING! Trust me, if you build it, they will buy, myself included! Thank you again for asking our community about our interest in making even better use of your product!