[Premium-Rx] AR7030 sopplementary information

[Raymond Boute]

Dear AR7030 users,

I also appreciate the AR7030. The following information may be useful.

(a) The "human interface" has often been criticized. Personally, I 
also prefer more parameters displayed and directly adjustable from 
the front panel. Despite its frugality in the display and the knobs, 
the AR7030 is quite well-designed: frequently-used functions are most 
quickly accessed.
   A disadvantage is that, after not using the AR7030 for a long 
time, one must learn again where those functions are hidden. The 
manual is quite verbose, and for some functions the relevant 
information is scattered over many sections.
   Therefore I prepared the attached "Quick reference guide". 
Comments and suggestions for improvement are appreciated and will be 
incorporated in a later version as time permits.

(b) A technical design problem is that frequency increments are 
multiples of a power of 2. When zapping with the IR control in 1 kHz 
increments, after a few steps the frequency is off and one must 
readjust with the knob.

(c) When I got the unit a few years ago, the frequency was off about 
100 Hz because the TCXO had drifted to a lower value and could not be 
raised enough by the adjustment trimmer. Removing the parallel 
capacitor made the frequency a bit high and it could not be lowered 
enough. I was not inclined to experiment with SMD capacitors...
   Fortunately xieqq2012 on eBay offers custom-made TCXOs at about 
$20 that happen to be pin-compatible and quite accurate (within .1 
ppm measured with a GPS disciplined counter). The weblink is
https://www.ebay.com/itm/TCXO-0-1ppm-Crystals-Oscillators-Clock-Frequency-can-be-customized-/182144121804
It is best to contact the seller in advance to specify the frequency.

I wish everyone good health in these hazardous times.

73
Raymond ON4DBV