RX issues solved more?

Well.. after talking with George Heron by e-mail, he was thinking that I probably still had issues with the SoftRock.

Some good diagnosing information was measured by George.  I did turn out that I was -11 dB from his Softrock 6.3 RX TX with my sr63ng.  I went through and verified that I had strong LO from the 74AC74 divider and then.. well got fed up and reflowed all of the RX stage components.

It seemed to bring up the gain to within a dB or two of George's unit.  I need to verify with at least one more test that I have it A-OK quantitatively (measure with the signal generator and the oscilloscope again).. but the initial test George proposed (50 uV "S9" or -73 dBm @ 50 Ohms) should just peak the bandscope with the RX Atten setting at 2.0 dB.  It does do that now.  It seemed about 12 dB off before from the units' own RX Atten scale.  Measuring 11 dB on lab equipment (8640B and a Tek 2235 Scope) when I guessed 12 dB from the rig and George's test description is a testament to the care taken in the design of the gain distribution on the rig.

I should also say that the late evenings I've been working with the radio.. have had pretty bad band conditions..  so I've done some SWL with it as well.  Of *any* radio I've used LSB/USB to listen to AM on this one sounds the best.  This includes (IMHO) the Flex-1500 and Flex-5000.  There has been a lot of thought in the DSP in the SDR-Cube, and it shows.  It is REALLY clean.  Once it gets some AGC, it will be unbeatable.

I also ordered off the CCI AN-762 amp I posted about previously.  So the beginnings of an 100W+ amp that I've always wanted to build for all of my QRP rigs is coming in 3-4 days.

I'm going to design a replacement plug in card for the TX PA (PAF) that is broadband and more like 3-5W out to the amp.. I'll get there eventually.. I don't think I could handle a kitting operation like George but I will make the design open.

Ultimately I'd like to design a sr63ng type rig, but with a PA and filters on one board like the MOBO.. but without all the plug in's.. maybe I'll get to in in 2011.   Maybe not..

I'll try to tackle the "Electronic Origami" that assembling the Cube is and test the 20m/30m PA I built in the next several days.

I did put a right angle connector on the I2C connection on the DSP board.  I'll upload a picture of it later when I screw all of the fun stuff back together and start packing up the SDR-Cube.

Until next time..