[Premium-Rx] Cubic 3030 info requested.

Sat Nov 19 17:44:30 EST 2005

Hi Hans,

Responses one by one:

You are probably right on the 1st IF filter being 20 KHz.  The 16KHz is typically a straight-through path on the 2nd IF Filter board.  That is, you get 5 filters, plus the 6th is actually the 1st IF bandwidth combined with tuned IF amps.

OK on the firmware--I'm not familiar with it, but that means nothing.  NOTE:  every time a customer changes the filter order, the firmware changes because the readout values are hard-coded into the firmware.

Keypad bounce is related to the panel interface--look for a big tantalum cap---if it is orange orange orange, it's a pre-fix module.  If you add about 4.7uf in parellel, you'll be much less bouncy.

Those IF converters are great!  Hold on to this one.  You're right---it's set up for DSP/SDR, etc.

I'm surprised the S meters match-the receivers are usually way out of wack with respect to each other AND other chassis as well.  I've been working on a series of modifications that make the receiver more pleasant to use and listen to.  I'm having good success thus far.  The mods solve bouncy keypads, noisy idling rx's, digital EMI radiated by rx, S meter alignment, etc.

OK on the GPIB--you can get cheap GPIB controller boards on ebay-current drivers available through HP or National Instruments.

The rhytmic clicking is the hour meters...these perform no useful purpose for the hobbyist, so you can silence the clicking by disconnecting the meters.

The noise issue is certainly subjective--if it bothers you, look at the diagram of the IF amp in the detector module--note the chip's AGC pin is strapped directly to ground--full gain (>55db).  This is the source of noisy idle.

The agc is the "hang" type--very annoying when trying for ssb/cw.  If you soften the bleed resistor (raise value), you can change the pumping effect to closely resemble the typical decay of plain old agc...this is much easier to listen to.  AGC pickup and 1st IF attenuator engagement can be realigned as desirec, thus giving you control of the agc curve overall.

study the receiver and note all your questions---the R3030 series is very handy for the hobbyist, as circuitry is discrete enough that it can be worked on without any unusual equipment or skills.  You can tailor many aspects of the rx to meet your preferences.

regards

John Collins
___________________________________________

  ----- Original Message ----- 
  From: Hans.Hamradio 
  To: John 
  Cc: premium-rx at ml.skirrow.org 
  Sent: Saturday, November 19, 2005 12:46 PM
  Subject: Re: [Premium-Rx] Cubic 3030 info requested.

  Hi John and the group.

  Tnx for reply on above subject.
  I got some further info available. Your reply is very much appreciated.

  IF filters according to the display: 0,5 - 1 - 2 - 4 - 8 - 16 kHz. In the IF module there are 5 Collins mechanical filters. Since it has a 16 kHz BW, I assume the roofing filter (1st IF) is 20 kHz. 

  CPU firmware according to the sticker: "R3030 V2-2 9-17-85". So it should be a 3030 with FW Ver.2.2, I guess.

  Keypad is indeed a little bit bouncy.
  There is an IEEE-488 I/F.
  It has the TCXO - I can hear the relays clicking rhythmically.
  It also has IF converters to about 15 kHz. (Nice for SDR and DRM).
  The S-meters are matching pretty well.
  The noise on a clear channel is not more than some other receivers I have.
  I am not pleased with the AGC in SSB/CW mode. I reacts much too quickly to noise spikes, and effectively mutes the receiver. In AM it seems to be better.

  Regards Hans/PT

    ----- Original Message ----- 
    From: John 
    To: Hans.Hamradio 
    Cc: premium-rx at ml.skirrow.org 
    Sent: Thursday, November 17, 2005 11:42 PM
    Subject: Re: [Premium-Rx] Cubic 3030 info requested.

    Hi Hans,

    I'll take a chance and guess you've got something along the lines of a 2411...essentially a military/gov spec'd R3030.  What IF filters does it have?  Just give the readout values-don't break any module inspection stickers yet.  The base R3030 has CPU firmware version 4.7A, non-bouncy keypad (tell me if your keypad is bouncy), 10KHz 1st IF filter, 0,5/1/2/4 KHz 2nd IF mechanical filters, MS-style connector, no speaker output (you can add one), and a 2nd gen keypad with a different keypad layout than the more common R3030A.  If you download the R3030 / 3080 manual on Premium-RX web site, you'll have almost everything you need by way of info.

    If I'm not mistaken, list members own 6 different versions of the R3030 series.  They differ in firmware versions, remote control species (GPIB/Serial/Parellel), 1st & 2nd IF filters, rear panel I/O, and test/external processing outputs.  There's also a 1/2 wide single receiver called the R3080.  Very slick - similar idea to the Racal 6830.   The basic receivers are virtually identical.

    Does your receiver seem very noisy when idling on an empty channel (antenna connected)?   Do the left and right "S" meters not match?  These problems and more can be fixed rather easily.

    in the longer term, I wish you best of luck with the receiver.

    John Collins
    _____________________________________________
      ----- Original Message ----- 
      From: Hans.Hamradio 
      To: John 
      Cc: premium-rx at ml.skirrow.org 
      Sent: Thursday, November 17, 2005 3:33 AM
      Subject: Re: [Premium-Rx] Cubic 3030 info requested.

      Hi John and other repliers to my request.

      Tnx for great response and support.
      As requested there is some further information made available which will clarify/help:

      The memory chips in both CPU modules have a red circular sticker with "R3030 V2-2 9-17-85". There is also a white sticker on the top of the module saying "PROGRAM MEMORY 2143-3110"

      The CPU modules are marked like this:

      Assy No. 2140-1110, S/N 30585-30 
      Assy No. 2140-1110, S/N 30685-30

      The IEEE-488 module is marked like this:

      Assy No. 2140-1112, S/N 05385-30

      The top cover is marked: R-3030 (V). Apparently there has been a military type tag under the left front handle, but this has been removed.

      It does not have a fan, and it has the MS type audio connector (military round multipin).

      Regards and thanks in advance for the reply.

      Hans

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