Re: suggestions for a graphics display

Arv Evans


You have echoed my feelings about CAT interface, except that i would think it needs to evolve instead of being thrown away.  CAT as a link interface may be adequate.  It is how we use the data that is woefully outdated.  Maybe this warrants a specific thread, or possibly a new discussion group that is focused on bringing CAT into the modern world?

The 128 x 64 LCD displays are easy to control.  If the supply is stable they could be a good near-term solution.


Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------
From: Ashhar Farhan <farhanbox@...>
Date: 2/15/19 7:29 PM (GMT-07:00)
Subject: Re: [BITX20] suggestions for a graphics display

The tft displays are a plenty, however, their supply is erratic and the quality ranges from superb to unknown. There is the matter of noise emission and current consumption too. After aruging for every milliamp on the RF side, it would be a travesty to give up all of it on the display.

Doug and others,
I am continuing to investigate the e-ink. I have two displays, both from waveshare with me. One is a 2.9 inch display and the other is a 1.54 inch display. Lets see, it appears to be that if the display coulf offer 3 updates of tuning frequency per second, we'd be home.

Thanks for the sugesstion for CAT. A CAT lile protocol that does more is needed. Given the plethora of modes that we run these days, CAT should have retired 20 years ago. It can't even send morse code or turn the beam, leave alone 'decode psk31 at 1200 hz'. 

Given my personal inclination, i am still tempted for the geneic 128x64 monochrome LCD display where i can switch the backlight off and on. The display is available to builders in Bangladesh as well as Sacramento. Unfortunately, it is not pimped enough. It is bland. Somewhat like the K3 display.

Let me play with the tft displays today and measure the current and noise.

- f

On Sat 16 Feb, 2019, 7:44 AM Arv Evans <arvid.evans@... wrote:

Have to admit that it was necessary for me to Google "BLE" to find that it just means
Blue-tooth Low Energy.  That is interesting, and provides input for more thought and
possibilities.  Maybe use the nth harmonic of a fairly low frequency crystal and add 
the necessary frequency hopping by warping the crystal oscillations with a varactor...?

BLE, or something similar, could provide the physical and data format part of a Phone-
to-radio link.  We would still need the control application on the phone and a matching
control implementation on the ham radio equipment, but there are already some CAT
style interfaces for cell phones.  Making them work over wireless BLE is an interesting


On Fri, Feb 15, 2019 at 4:27 PM Tom, wb6b <wb6b@...> wrote:
Another possibility would be to forget the display (or have just a minimal display) on the radio and make the radio a BLE device. That way any smartphone could be the display and control. 

Tom, wb6b

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