New USB interface for HF digital modes by MFJ

Discussion in 'Amateur Radio News' started by KJ4YZI, Mar 13, 2017.

ad: L-HROutlet
ad: l-rl
ad: L-rfparts
ad: Subscribe
ad: l-gcopper
ad: l-assoc
  1. KD2GIY

    KD2GIY Ham Member QRZ Page

    That's what I'm saying, MFJ STEP YOUR GAME UP !
     
    N7AFB, W0OLL and K3RW like this.
  2. AD0AC

    AD0AC XML Subscriber QRZ Page

    Jessie. Trying to set up svxlink.
     
  3. AD0AC

    AD0AC XML Subscriber QRZ Page

    Looks like they threw an EagiDigi, a cheap USB sound dongle, and a couple of 10k pots in a box, and are charging $100 for the privilege. Mississippi engineering at its finest.
     
    N7AFB, K9PLG and K3RW like this.
  4. KI7ANF

    KI7ANF Ham Member QRZ Page

    WHINERS
     
  5. KA1BSZ

    KA1BSZ Ham Member QRZ Page

    the MFJ 1275 is by the better working device here. I have 2 of the MFJ 1275 and they have worked flawless!!!!!! I couldn't ask for better product!!!!! I wouldn't trust this new product! I'd stick with the 1275 or a signal link.
     
  6. KA1BSZ

    KA1BSZ Ham Member QRZ Page

    nope..don't buy this ...get the MFJ 1275 it is worth the money! no need to buy extra cables, just plug into your computer sound ports,radio ext speaker port,adjust the jumpers,adjust the the internal sound card in your computer, adjust the mic gain ( NEVER LET THE ALC SHOW ) set the switch where it says input to " both " and use the vox and start with the radio @ 100 watts and use the mic gain control to maintain lowest power setting and use the audio settings on the computer. PLEASE NOTE: there are different settings for other bands AND other modes. modes like JT65 and JT9 the audio settings are a little tricky. de KA1BSZ/M OLIVIA 8/500 14.072 DAILY!
     
  7. WD4ED

    WD4ED Ham Member QRZ Page

    That is a $25 device. Tops.
     
    AD0AC likes this.
  8. KC2QQR

    KC2QQR Ham Member QRZ Page

    I like my Signalink... just way too easy to set up, and the manual controls on the front make it nice. One thing I love about the Signalink is the fact that there is a ON/OFF switch on it... I don't know how many times I would've accidentally keyed up my rig if it wasn't for that simple feature! It's almost like a safety on a firearm. :)
     
    N7AFB and KF5RHI like this.
  9. WA7LTR

    WA7LTR Premium Subscriber QRZ Page

    SignaLink does not support 9600 baud. The 1204 does. Considering one of these for VHF due to the higher baud rate capability.
     
  10. KM4JOJ

    KM4JOJ Premium Subscriber QRZ Page

    Uhh...how?

    I will be the first to admit; I am *not* a fan of Signalinks or any of these already made solutions because they're way too expensive for what they put in to it. But the Signalink is literally just a more complicated version of this; it's a sound device linked through isolation using a much more complicated method of PTT triggering. I can't see *any* technical reason...being just a sound card...that the device wouldn't do 9600 baud. Well..ok..I take it back. If they used really cheap transformers that had a limited bandwidth; I could see 9600baud failing. Having never seen one on the spectrum, I don't know how much audio bandwidth it consumes.

    But if that's the only reason...then it's a pretty easy one to get around; but you would think for the price you pay...they'd use full-bandwidth isolation transformers.

    Looking at this schematic for the 1204...it makes zero sense. It looks like a basic voltage-doubling VOX circuit I've seen designs for. Audio isolation transformer seens to have multiple secondary taps...with the VOX circuit pulling off the "highest" part of the secondary. That helps aleviate some problems of not having enough current to trigger and the VOX circuit pulling the audio down; but these are all fixed values. You are at their mercy of what the delay is set to.

    That is *no better* than using VOX on a rig with a direct audio cable to a computer.

    You can build the same thing for close to 1/10th of the price; and you can really get it down to 1/10th if you go the physical hardware control route and use a serial dongle with RTS.

    I guess this will just put a few more people on digital modes with the things set to "Default Devices" so we get system sounds and JTAlert coming over the band.
     

Share This Page

ad: w5yi