HFU HF Underground

Technical Topics => Equipment => Topic started by: R_Duroid on July 10, 2016, 1143 UTC

Title: Car Shortwave radio
Post by: R_Duroid on July 10, 2016, 1143 UTC
Anyone using the BST-1 car shortwave radio?  Sounds like a nice way to get shortwave in car with no external boxes or mods to car.

Title: Re: Car Shortwave radio
Post by: redhat on July 10, 2016, 1507 UTC
This looks like a good solution to the problem of the lack of availability of in dash shortwave receivers, at least domestically.  My kenwood in the X-mobile has shortwave, but it came off ebay from some guy in Israel, and this seems to be the norm these days.

The Prof and I were thinking about building a bluetooth shortwave receiver with sync AM and stereo decoding.  It would certainly be possible with todays technology, you just need to find the right guy with the know-how.  The nice thing about bluetooth is all the controls for the receiver would be available on your bluetooth car stereo, including signal strength and presets.

Something to consider...

Title: Re: Car Shortwave radio
Post by: skeezix on July 11, 2016, 0233 UTC
My car also has a shortwave car stereo, a Pioneer DEH-X4750BT. Bought it recently from (more than likely) the same guy in Israel. A few years ago, bought a Sony CDX-GT570S from him and used that until a few weeks ago. Both radios have compromises, and I'm relatively satisfied with them. Tuning can be a pain.

Having a control with Bluetooth would be great, as then could have the ability to write an app for a smartphone for controlling it easily (and maybe even integrating it to online skeds).

Sync AM & AM stereo in the car... that would be great. So great.
Title: Re: Car Shortwave radio
Post by: R_Duroid on July 12, 2016, 1554 UTC
Well, I ordered a BST-1 so I'll report on how it works.  Supposed to be here July 13.
Title: Re: Car Shortwave radio
Post by: Pigmeat on July 14, 2016, 0340 UTC
I heard good and bad things about the Sony, but there was a guy in Quebec who used to post here, that got some amazing MW dx results using one. My guess is people expected too much from the things and probably didn't install them properly to begin with, ie; proper grounding and a noise filter? Short antennas combined alternator noise aren't exactly conducive to rolling dx.
Title: Re: Car Shortwave radio
Post by: Pigmeat on July 14, 2016, 1317 UTC
Redhat, if you see the Professor, ask him how he kept the batteries in that radio working for so long during his island years?
Title: Re: Car Shortwave radio
Post by: redhat on July 14, 2016, 1508 UTC
Will do Pigmeat :)

Title: Re: Car Shortwave radio
Post by: R_Duroid on July 21, 2016, 0046 UTC
Well, I got the BST-1 in 3 days after ordering.   Two words - Pretty nice. 

You'd never know you have shortwave in the car, other than the 24" whip on the trunk.  Nothing in the front seat at all.  I keep the Key Fob controller in my ashtray since my car is electronic start, no real key hanging from the dash.   To listen to shortwave, I just tune to 88.5 on my FM radio.

I'm using in a 2012 Infinity G-37.     Put radio in the trunk and antenna on trunk lid.  Took about 10 minutes to put on antenna.    It came on 88.5 FM and that was good clear frequency for my area, so didn't have to change it but I've experimented with changing freq with the key fob and it is easy.  It's in a nice solid extruded aluminum box.  The power cord is long, about 10 feet and was ok to get from my front seat power outlet through the flip down opening to my trunk.   I bought their antenna and it is some stainless steel trunk clip type with a 24" long whip.  The cable is about 6 or 7 feet and plugs right into the BST-1.

It was on 15 MHz when I turned it on.  I heard WWV here in GA in middle of day.  S meter read S6.  Lots of stations when going through the presets.    The RDS readout is nice, you get the HF frequency and preset number when you change channels and then after a few seconds the preset number changes to the S meter reading from 1 to probably 9.  I've not seen anything bigger than 8 and that came from 7315 WHRI in the afternoon.   The AGC seems good, no real difference in audio levels between S1 and stronger signals.   

Audio is very nice, about same volume as any FM station and if you set the bandwidth to music, it really opens up.  The oldies show on WTWW on 5085 at night really sounds good.  Fidelity better than the AM radio in the Infinity.   Seems to have good low frequency audio response as I can hear the 100 Hz time code buzz on WWV when signals are strong.

I can listen to The Power Hour during the 8-9 AM time as I drive to work.  This is 7490 from WWCR.  Very decent signal.  It is shortwave, some fades and noise here and there but very impressive while driving.

Haven't had any car noise that I can tell but I haven't done extensive tuning around.  I think the antenna way in the back helps plus it get grounded by the set screws on the clip mount that punch through the paint to the metal.   

Seems very sensitive and selectivity is OK.    At night I can hear Overcomer on 5015 from WRMI at about S3 against Cuba music on 5025 that gets up to S6.  Seems to separate them OK but you can hear some splatter from the Cuba station.  I think that is the Cuba transmitter not the radio but need to compare with my Kaito.

At night, it is really nice while driving, lots of stations from Europe.   3885 Ham AM Calling frequency has lots of activity.   9420 Voice of Greece very good signal with music.  You can see the fades from the S meter moving around but audio stays pretty level.  Also it has some CB channels in preset, #6 is CB Channel 6, the one with the high power Dx'ers and I was listening to some locals.   

Once you figure out how to tune it manually, you can tune any station you want that isn't in the preset as it comes from factory.  Adding new frequencies to the preset is easy.  Once you find a new frequency you want, you hold the top button down for 4 beeps and then you get some kind of Morse code message and the display will show a new preset number for that frequency.

My car switches the power to the power outlet so it always starts up when turning on engine.  I can see some type of SW version info that shows at power up.   Everything important is saved in memory when you power down, so it will start back up on same frequency and audio bandwidth, FM transmit frequency, etc. 

When you are scanning in preset, you can hear a bit of background noise at it tunes so you can tell it is doing something, but it isn't annoying.   I took the antenna off and ran the scan and it took 20 seconds to go through all of the 50 channels or so that are in the preset as it came from factory.   I notice that it will stop on very weak but just listenable signals and they always read S1.    If you are listening to something and it goes off the air, the S meter reads S- and in about 3 seconds the radio will completely mute the audio.   

I need to run some sensitivity comparisons between the BST-1 and my Kaito KA1103.  Going to use batteries in the Kaito and and hold it outside car, up near roof and do A/B comparison on what I can hear on each one.  More info to follow after I use it some more.
Title: Re: Car Shortwave radio
Post by: redhat on July 21, 2016, 0520 UTC
Both Cuban outlets on 5025 and 5040 (I think?) are running 10 KHz audio, and they do tend to splatter over each other and other stations.  That is not the fault of the radio...

Sounds like a neat toy!

Title: Re: Car Shortwave radio
Post by: Pigmeat on July 22, 2016, 0206 UTC
Same here. I can leave antennas down on the portables and they still blast in.
Title: Re: Car Shortwave radio
Post by: R_Duroid on July 26, 2016, 0032 UTC
OK, did some A/B comparisons with my KA1103 on batteries sitting on top of car.  It was in DX mode and narrow selectivity.  I had the whip all the way up which is about 24", same as the whip on the BST-1.   The BST-1 was in HI SENS mode.

I turned on car engine and let idle.  I tuned the KA1103 to the memory channels in the BST-1 and compared results.  If I heard it on the KA1103, I could hear it on the BST-1.  The frequencies in memory in the BST-1 are on www.carshortwaveradio.com  under "memory channels".   

This first test was at about noon local or 0400 GMT.  This was mostly 9-21 MHz but I could hear 5025 from CUBA and 5015 in Florida plus CB Channel 6 which is 27025.   The big difference was the lack of ignition noise on the BST-1.  The KA1103 had popping sound that only went away if I moved it about 6 feet away from the car.

At night, 9 PM EST or 0100 GMT, lots of activity on the 3-9 range.  Same as daytime, if I heard it on the KA1103, I could hear it on the BST-1.

The BST-1 has much better AGC than the KA1103.  The volume is near constant from very weak to strong stations where as with the KA1103, you have to adjust volume up or down.

In summary, it seems the BST-1 must meet the 1 microvolt listed sensitivity and anything you can hear on a typical shortwave portable with a whip you can hear with the BST-1.   For car use, the noise blanker like in the BST-1 is really needed.

I'm going on long road trip to NM in August and will get a good chance to give the BST-1 a workout.

Title: Re: Car Shortwave radio
Post by: Pigmeat on July 26, 2016, 0414 UTC
Does the BST-1 come in metal case? If it does, it might explain why you didn't get the dreaded click with it.
Title: Re: Car Shortwave radio
Post by: R_Duroid on July 27, 2016, 0117 UTC
Yes, in a nice extruded aluminum case.  This isn't my unit but found picture of it on a review on SWLing blog.

Title: Re: Car Shortwave radio
Post by: R_Duroid on September 03, 2016, 1330 UTC
I really put the BST-1 to the test. Installed it in a rental car. Drove from Atlanta area to Grants, New Mexico and back.  Heard my Southeast AM net on 7295 while in New Orleans outskirts during the day.  These are ham rigs 100 watts in Georgia and Alabama and Florida. The BST-1  performed great.   Shortwave all the way there and back.
Nighttime driving was very interesting with lots of European and South American stations on 9 MHz band and 6 MHz.   Daytime, I heard the usual US stations plus Saudia Arabia and Europe in the later afternoon on 7 MHz band.  Voice of Greece on 9420 starts with very interesting music about 2300 GMT and is about S4 on the meter which is very listenable signal.    Radio Romania blasts in on 9730 at 0000 GMT.   The S meter on the FM radio RDS display is very interesting.  It bounces around from S3-S8 on Radio Romania but audio level stays very constant.
I also listened to CB.  Preset channel 6 is CB channel 6, the high power Dxer frequency and lots of skip activity there.  Also has Channel 17 and 19 on presets 17 and 19.  These are the truckers North South and East West frequencies.  Always some activity there on the highway.  Sensitivity seems ok there, more than enough to hear trucks ahead and behind me.  This helped out on one big delay up in West Texas from an accident. 
I did have to switch the FM freq as I started to get into an area where there was a FM station on my current FM freq.  You can tell this is going to happen as the RDS display gets sluggish before the BST-1 audio ever gets taken over by the stronger FM stations you are driving to.    4 beeps on the keyfob bottom button and it starts beeping for a few seconds on each FM freq as it sequences through the 4 FM channels and you hit any button to lock it there.   Never had any problem finding a clear frequency out of the 4 choices.
Overall, quite a lot of performance for the $.  I put on the antenna in about 3 minutes on the trunk lip of the rental and just put the radio in the back seat and plugged into the car power outlet and it was working.  No ignition noise problems.