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<font size="5" face="Comic Sans MS">I snatched this from AI
(Gemini). <br>
<br>
Q: </font>Can you put expresslrs on the 1.2 gig ham band?
<div
style="font-weight: 400; overflow-wrap: break-word; margin: 16px 0;"><mark
style="font-weight: bold; background: #D3E3FD;"><span
style="font-weight: bold;">No, you cannot put ExpressLRS on
the 1.2 GHz (23cm) amateur radio band.</span></mark></div>
<div
style="font-weight: 400; overflow-wrap: break-word; margin: 16px 0;">While
the 1.2 GHz / 1.3 GHz spectrum is highly valued by HAM radio
operators for long-range analog and digital FPV video
transmitters, <span style="font-weight: bold;">the ExpressLRS
firmware cannot be ported or built to operate on this frequency.</span><span>
[1, 2] </span></div>
<div
style="font-weight: 400; overflow-wrap: break-word; margin: 16px 0;">The
limitations preventing an ELRS link on 1.2 GHz stem from hardware
constraints rather than software blockages:</div>
<h2 style="font-size: 20px; font-weight: 600;" role="heading">1.
Complete Absence of 1.2 GHz LoRa Microchips</h2>
<div
style="font-weight: 400; overflow-wrap: break-word; margin: 16px 0;">ExpressLRS
relies fundamentally on <span style="font-weight: bold;">Semtech
LoRa hardware transceivers</span> to achieve its extreme long
range and high packet sensitivity.<span> [3] </span></div>
<div>
<div></div>
<ul>
<li><br>
</li>
<li>Semtech only manufactures these chips for specific global
ISM bands: the <span style="font-weight: bold;">SX1280</span>
series handles 2.4 GHz, the <span style="font-weight: bold;">SX1276/1262</span>
series handles 868/915 MHz, and the older <span
style="font-weight: bold;">SX1278</span> chips or newer <span
style="font-weight: bold;">LR1121</span> architectures
handle Sub-GHz frequencies like 433 MHz.<span> [4, 5, 6] </span></li>
<li>Semtech does not make a LoRa chip that natively covers or
tunes to the 1200 MHz–1300 MHz spectrum. Because ELRS code is
entirely hardwired to leverage the inner logic of Semtech's
LoRa modems, you cannot run ELRS on non-LoRa RF hardware.</li>
<li><br>
</li>
</ul>
</div>
<h2 style="font-size: 20px; font-weight: 600;" role="heading">2.
Fatal Interference with GPS (The Harmonic Issue)</h2>
<div
style="font-weight: 400; overflow-wrap: break-word; margin: 16px 0;">Even
if custom RF mixing or up-converting hardware was engineered to
push an ELRS signal into the 1.2 GHz band, it would be highly
impractical for RC flight. The <span style="font-weight: bold;">1.2
GHz Ham band sits directly adjacent to the GPS L1 frequency
(1575.42 MHz) and overlaps the GPS L2 frequency (1227.60 MHz)</span>.</div>
<div>
<div></div>
<ul>
<li>1.2 GHz video transmitters are notorious for immediately
blinding or wiping out GPS locks on drones unless heavily
filtered and physically separated from the GPS puck.<span> [7]
</span></li>
<li>Because an ExpressLRS transmitter on a drone (the receiver)
sends heavy telemetry bursts back to your handset, a 1.2 GHz
ELRS transmitter on board would permanently blast out your
drone's GPS module, stripping your aircraft of crucial
navigation and rescue features.<span> [3] </span></li>
</ul>
</div>
------------------------------------------ Me, not
AI------------------------------------<br>
<font face="Comic Sans MS" size="5">There are plans and kits. </font>
<div></div>
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<br>
<div class="moz-signature">-- <br>
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