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Stryker sr94hpc

Discussion in 'Amateur Radio Modifications' started by dxing440, Jan 19, 2017.

  1. dxing440

    dxing440 Active Member

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    Anyone moded one of these for 11 meter? L45 jumper is not it, unless theres more to do afterwords. Thx


     

  2. larryk40c

    larryk40c Member

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  3. larryk40c

    larryk40c Member

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    Cut the little white wire on the board. You can't miss it
     
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  4. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    There is some free software from Stryker. I think you would have to buy the cable unless someone knows how to make it.
     
  5. peabody830

    peabody830 Active Member

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    1、Remove L45 line (White Wire)

    2、Hold [FUNC]+[FP6] when you power on the radio,when LCD displays band, release keys.

    3, turn channel knob to choose a band;

    4、Long press [PUSH] to confirm ,when LCD displays “RESET MPU PLEASE

    WAIT”,release PUSH
     
  6. Iceburgh

    Iceburgh New Member

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    Anyone attempt any other mods on the SR-94HPC? Looking for the modulation limiter to be able to disable and enable it with a switch. Modulation is flat topping way before 100% modulation.
     
  7. peabody830

    peabody830 Active Member

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    why would you do this, most of the time you hear a Stryker radio over mod it sounds like crap
     
  8. Iceburgh

    Iceburgh New Member

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    Well are you talking about this radio being overmod, or a different stryker radio? Since this radio doesnt yet have a mod limiter removal mod yet, you must be talking about another stryker radio model. They are not all the same. Any radio with tbe mod limiter taken out and the input audio is too high like using a power mic that is turned up too far will sound over mod bexause it is over mod. Im talking about this model sr94hpc only.
     
  9. davew41

    davew41 Member

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    I have one of these, and want to back the am modulation down, can not find what W it is anywhere anyone have a service manual on these? or what each of the W labeled vr's do?
     
  10. Dmans

    Dmans Well-Known Member

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    davew41,

    Video below explains it about the 12:00 mark or so.



    73's
    David
     
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  11. Shockwave

    Shockwave Sr. Member

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    Most modulation limiters prevent distortion. However, the one in the SR-94HPC simply prevents good performance. After reading people rave about this radio "having the strong AM audio Stryker is known for", I bought one. What a disappointment. It has the strongest modulation limiter is more like it.

    This lack of strong modulation was not acceptable so I looked around for a schematic to no avail. When that didn't work I pulled the board and tried tracing the circuit from the mic input looking for the attenuation transistor. This board may be three layers because lots of traces disappear from the top of the board to the bottom. Like connections must be happening in the middle.

    When that failed, out came the scope to trace the audio from transistor to transistor. Luckily, the desired one is on the top of the board. On the extreme front edge of of the board to the right of the white ribbon cable is a transistor. Two legs face the front edge of the board while one faces the rear. It's the leg on the right front edge of the board we are concerned with.

    Solder a 470 ohm resistor to the pin on the bottom, right side of the transistor and ground the other side of the resistor. You could use the screw in the right front corner of the board to ground this side of the resistor. This loads the drive triggering the transistor to conduct and was the safest way I could find to increase the range of both AMC controls without defeating the AMC. It will distort if defeated.

    Now the radio screams like 45 watts PEP should. Plenty of range on the controls so they can be set on the scope without distortion. If someone wants to post a detailed picture of this area of the board, I'll point out the location of this transistor a bit better. You should remove the ribbon cable and front panel when installing this resistor otherwise the soldering iron may burn both.
     
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  12. Eldorado828

    Eldorado828 Active Member

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    That's it right there! That's for both the SR-94HPC and the Anytone Apollo both of which are the same radio. It's pretty simple after you know what do do.
     
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  13. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    Apollo. Now I have to look it up. Lol
     
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  14. Eldorado828

    Eldorado828 Active Member

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    I apologize, it's the anytone Apollo II
     

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