Skip to Content
Version 134.1 by Kilight Cao on 2023/01/07 09:07
Show last authors
1 (% style="text-align:center" %)
2 [[image:image-20220620202334-2.png||height="467" width="809"]]
3
4
5 (((
6
7
8
9 )))
10
11 **Table of Contents：**
12
13 {{toc/}}
14
15
16
17
18
19 = 1. Introduction =
20
21 == 1.1 What is LPS8v2 ==
22
23
24 (((
25 (((
26 The LPS8v2 is an (% style="color:green" %)**open-source LoRaWAN Gateway**(%%). It lets you bridge LoRa wireless network to an IP network via (% style="color:green" %)**WiFi , Ethernet or Cellular Network**(%%) (via Optional 4G module). The LoRa wireless allows users to send data and reach extremely long ranges at low data rates.
27 )))
28
29 (((
30 The LPS8v2 is fully compatible with LoRaWAN protocol. It supports different kinds of LoRaWAN Network Connections such as: (% style="color:green" %)**Semtech UDP Packet Forwarder, LoRaWAN Basic Station, ChirpStack MQTT Bridge**(%%), and so on. This makes LPS8V2 work with most LoRaWAN platforms in the market.
31 )))
32
33 (((
34 LPS8v2 also includes a (% style="color:green" %)**built-in LoRaWAN Server and IoT server**(%%), which provide the possibility for the system integrator to deploy the IoT service without cloud service or 3rd servers.
35 )))
36
37 (((
38 Different countries use different LoRaWAN frequency bands. LPS8v2 has these bands pre-configured. Users can also customize the frequency bands to use in their own LoRa network.
39 )))
40
41 (((
42 LPS8v2 supports (% style="color:green" %)**remote management**(%%). System Integrator can easy to remote monitor the gateway and maintain it.
43 )))
44
45
46 == 1.2 Specifications ==
47
48
49 (% style="color:#037691" %)**Hardware System:**
50
51 * CPU: Quad-core Cortex-A7 1.2Ghz
52 * RAM: 512MB
53 * eMMC: 4GB
54
55 (% style="color:#037691" %)**Interface:**
56
57 * 10M/100M RJ45 Ports x 1
58 * Multi-Channel LoRaWAN Wireless
59 * WiFi 802.11 b/g/n
60
61 (% style="color:#037691" %)**Operating Condition:**
62
63 * Work Temperature: -20 ~~ 65°C
64 * Storage Temperature: -20 ~~ 65°C
65 * Power Input: 5V, 2A, DC
66
67 == 1.3 Features ==
68
69
70 * Open Source Debian system
71 * Managed by Web GUI, SSH via WAN or WiFi
72 * Remote Management
73 * Auto-provisioning for batch deployment and management
74 * LoRaWAN Gateway
75 * 10 programmable parallel demodulation paths
76 * Pre-configured to support different LoRaWAN regional settings.
77 * Allow customizing LoRaWAN regional parameters.
78 * Different kinds of LoRaWAN Connections such as
79 ** Semtech UDP Packet Forwarder
80 ** LoRaWAN Basic Station
81 ** ChirpStack-Gateway-Bridge (MQTT)
82 * Built-in (% style="color:#037691" %)//**The Things Network**//(%%) local LoRaWAN server
83 * Built-in  (% style="color:#037691" %)//**Node-Red**// (%%)local Application server
84
85 == 1.4 Block Diagram ==
86
87
88
89 == 1.5 LED Indicators ==
90
91
92 LPS8-V2 has totally four LEDs, They are:
93
94
95 (% style="color:blue" %)//**➢ Power LED**//(%%)//: This RED LED will be solid if the device is properly powered//
96
97 (% style="color:blue" %)//**➢ ETH LED**//(%%)//:  This RGB LED will blink GREEN when the ETH port is connecting//
98
99 (% style="color:blue" %)//**➢ SYS LED**//(%%)//:  This RGB LED will show different colors in different states~://
100
101 // ✓ **SOLID GREEN:** The device is alive with a LoRaWAN server connection.//
102
103 // ✓ **BLINKING GREEN:** a) Device has internet connection but no LoRaWAN Connection. or b) Device is in booting stage, in this stage, it will BLINKING GREEN for several seconds and then with BLINKING GREEN together//
104
105 // ✓** SOLID RED:** Device doesn't have an Internet connection.//
106
107 (% style="color:blue" %)//**➢ WIFI LED**//(%%)//: This LED shows the WIFI interface connection status.//
108
109
110 == 1.6 Button Intruction ==
111
112
113 LPS8-V2 has a black toggle button, which is:
114
115
116 (% style="color:blue" %)**//➢ //Long press 4-5s  : **(%%)the gateway will reload the Network and Initialize wifi configuration
117
118 // **LED status: ** ETH LED will BLINKIND BULE Until the reload is finished.//
119
120
121 (% style="color:blue" %)//**➢ **//**Long press more than 10s:**(%%)**    **//the gateway will restore the factory settings.//
122
123 //**LED status: ** ETH LED will SOLID BULE Until the restore is finished.//
124
125
126 = 2. Quick Start =
127
128
129 The LPS8-V2 supports network access via Ethernet or Wi-Fi connection and runs without a network.
130
131 In most cases, the first thing you need to do is make the lps8-v2 accessible to the network.
132
133
134 == 2.1 Connects to the network and accesses the gateway Web UI ==
135
136 == 2.1.1 connect the network ==
137
138
139 === (% style="color:blue" %)**Method 1**(%%):  Connect via Ethernet with DHCP IP from the router ===
140
141
142 (((
143 Connect the LPS8-V2 Ethernet port to your router and LPS8-V2 can obtain an IP address from your router. In the router's management portal, you should be able to find what IP address the router has assigned to the LPS8-V2.
144 )))
145
146 (((
147 You can also use this IP to connect.
148 )))
149
150 [[image:image-20220622100129-1.png||height="332" width="1263"]]
151
152 === (% style="color:blue" %)**Method 2**(%%):  Connect via LPS8-V2 Fallback IP ===
153
154
155 [[image:image-20230107084650-2.png||height="310" width="839"]]
156
157
158 (% style="color:blue" %)**Steps to connect via fall back IP:**
159
160 ~1. Connect PC's Ethernet port to LPS8-V2's WAN port
161
162 2. Configure PC's Ethernet port has IP: 172.31.255.253 and Netmask: 255.255.255.252
163
164 As below photo:
165
166 [[image:image-20230107085904-4.png||height="443" width="361"]]
167
168 3. In the PC, use IP address 172.31.255.254 to access the LPS8-V2 via Web or Console.
169
170
171 === (% style="color:blue" %)**Method 3**(%%):  Connect via WiFi with DHCP IP from the router ===
172
173
174 [[image:image-20220622100542-2.png||height="369" width="1256"]]
175
176
177 Fill in the WiFi information by checking the box and clicking (% style="color:red" %)**Save&Apply**
178
179
180 [[image:image-20220622102702-6.png]]
181
182
183
184 **Wi-Fi configuration successful**
185
186
187 [[image:image-20220622102847-7.png]]
188
189
190 [[image:image-20220622102901-8.png||height="476" width="938"]]
191
192
193 == 2.1.2 Access Configure Web UI ==
194
195
196 **Web Interface**
197
198 Open a browser on the PC and type the LPS8-V2 ip address (depends on your connect method)
199
200
201 [[(% style="background-color:yellow" %)**//http:~~/~~/IP_ADDRESS //**>>http://IP_ADDRESS]](%%) or (% style="background-color:yellow" %)//**[[http:~~/~~/172.31.255.254>>http://172.31.255.254(]]**//(Fallback IP)
202
203 You will see the login interface of LPS8-V2 as shown below.
204
205 The account details for Web Login are:
206
207 (% style="color:#4f81bd" %)**User Name: root**
208
209 (% style="color:#4f81bd" %)**Password:   dragino**
210
211 [[image:image-20230106153501-1.png||height="367" width="894"]]
212
213
214 == 2.2 The LPS8-V2 is registered and connected to The Things Network ==
215
216 === 2.2.1 Select your area frequency ===
217
218
219 (((
220 First, you need to set the frequency plan in LPS8-V2 to match the end node we use, so to receive the LoRaWAN packets from the LoRaWAN sensor.
221
222
223 )))
224
225 [[image:image-20220622103332-9.png||height="485" width="938"]]
226
227
228 === 2.2.2 Get the only gateway EUI ===
229
230
231 Every LPS8-V2 has a unique gateway id. The ID can be found on LoRaWAN Semtech page:
232
233
234 [[image:image-20220622103355-10.png||height="698" width="949"]]
235
236
237 (% style="color:red" %)**Note: Choose the cluster that corresponds to a specific Gateway server address**
238
239
240 **➢ Europe 1:**  corresponding Gateway server address:  **eu1.cloud.thethings.network**
241
242 **➢ North America 1:**  corresponding Gateway server address:  **nam1.cloud.thethings.network**
243
244 **➢ Australia 1: ** corresponding Gateway server address:  **au1.cloud.thethings.network**
245
246 **➢ Legacy V2 Console:** TTN v2 shuts down in December 2021
247
248
249 [[image:image-20220622103956-12.png]]
250
251
252 == 2.2.3 Register the gateway to The Things Network ==
253
254
255 **Login to The Things Network**
256
257 [[https:~~/~~/console.cloud.thethings.network/>>https://console.cloud.thethings.network/]]
258
259
260 **Add the gateway**
261
262 [[image:image-20220622104252-13.png||height="511" width="953"]]
263
264
265 **Get it online**
266
267
268 = 3. Web Configure Pages =
269
270 == 3.1 Home ==
271
272
273 //Shows the system running status~://
274
275 [[image:http://wiki.dragino.com/xwiki/bin/download/Main/User%20Manual%20for%20All%20Gateway%20models/HP0C/WebHome/image-20220622102901-8.png?rev=1.1||alt="image-20220622102901-8.png" height="476" width="939"]]
276
277
278 == 3.2 LoRa Settings ==
279
280 === 3.2.1 LoRa ~-~-> LoRa ===
281
282
283 //This page shows the LoRa Radio Settings. There is a set of default frequency bands according to LoRaWAN protocol, and users can customize the band* as well.//
284
285 //Different LPS8v2 hardware versions can support different frequency ranges~://
286
287 * (% style="color:#0000ff" %)//**868**//(% style="color:black" %)//: valid frequency: 863Mhz ~~ 870Mhz. for bands EU868, RU864, IN865, or KZ865.//
288 * (% style="color:#0000ff" %)//**915**//(% style="color:black" %)//: valid frequency: 902Mhz ~~ 928Mhz. for bands US915, AU915, AS923 or KR920//
289
290 (% class="wikigeneratedid" %)
291 //After the user choose the frequency plan,  the user can see the actual frequency is used by checking the page (% style="color:#037691" %)**LogRead ~-~-> LoRa Log**//
292
293
294 (% class="wikigeneratedid" %)
295 [[image:image-20220616110739-1.png||height="372" width="682"]]
296
297
298 (((
299 (% style="color:red" %)//**Note *: See this instruction for how to customize the frequency band: **//(%%)**//__[[How to customized LoRaWAN frequency band - DRAGINO>>doc:Main.How to customized LoRaWAN frequency band.WebHome]]__//**
300 )))
301
302
303 == 3.3 LoRaWAN Settings ==
304
305 === 3.3.1 LoRaWAN ~-~-> LoRaWAN Semtech UDP ===
306
307
308 //This page is for the connection set up to a general LoRaWAN Network server such as [[TTN>>url:http://www.thethingsnetwork.org/]], [[ChirpStack>>url:https://www.chirpstack.io/]], etc.//
309
310
311 [[image:image-20220616111932-2.png||height="516" width="672"]]
312
313
314 === 3.3.2 LoRaWAN ~-~-> LoRaWAN Basic Station ===
315
316
317 //This page is for the connection set up to the TTN Basic Station, AWS-IoT, etc.//
318
319
320 [[image:image-20220616113246-3.png||height="396" width="672"]]
321
322
323 (((
324 Please see this instruction to know more detail and a demo for how to use of LoRaWAN Basic Station: __[[Use of LoRaWAN Basic Station - DRAGINO>>doc:Main.Use of LoRaWAN Basic Station.WebHome]]__
325 )))
326
327
328 == 3.4 Network Settings ==
329
330 === 3.4.1 Network ~-~-> WiFi ===
331
332
333 [[image:image-20220616114756-4.png||height="251" width="669"]]
334
335
336 === 3.4.2 Network ~-~-> System Status ===
337
338
339 [[image:image-20220820134112-2.png||height="539" width="668"]]
340
341
342 === 3.4.3 Network ~-~-> Firewall ===
343
344
345 [[image:image-20220616115351-6.png||height="244" width="661"]]
346
347
348 == 3.5 System ==
349
350 === 3.5.1 System ~-~-> System Overview ===
351
352
353 Shows the system info:
354
355 [[image:image-20220917144512-5.png||height="618" width="853"]]
356
357
358 === 3.5.2 System ~-~-> System General ===
359
360
361 In the System-> System General interface, Users can customize the configuration System Password and set Timezone.
362
363 [[image:image-20230107084158-1.png||height="543" width="844"]]
364
365
366 === 3.5.3 System ~-~-> Backup/Restore ===
367
368
369 [[image:image-20220917144725-6.png||height="208" width="869"]]
370
371
372 === 3.5.4 System ~-~-> Remoteit ===
373
374
375 In the System-> Remoteit interface, users can configure the gateway to be accessed remotely via Remote.it.
376
377
378 the users can refer to this link to configure them: **[[Monitor & Remote Access Gateway>>http://wiki.dragino.com/xwiki/bin/view/Main/Monitor%20%26%20Remote%20Access%20Gateway/?Remote%20Access#H2.1A0RemoteAccessviaRemote.it.]]**
379
380 [[image:image-20221230092303-2.png]]
381
382
383 = 4. Build-in Server =
384
385
386 The default factory version of LPS8-V2 is installed with the built-in Applicant server: (% style="color:blue" %)**Node-Red, and**(%%) LoRaWAN Server: (% style="color:blue" %)**The Things Network - Stack (Open Source 3.19 Version).**
387
388
389 [[image:image-20220820115644-1.png||height="217" width="778"]]
390
391
392 (% style="color:red" %)**Note:**
393
394 **Path**: System ~-~-> Built-in Server
395
396
397 **Troubleshooting:**
398
399
400 **~ 1. URL does not jump properly**
401
402 For the ttn-stack, you can click the update the URL which will update the configuration where change the hostname to the current local IP address as the URL.
403
404 For the Node-Red, you can use the local IP address and the port is 1880 to access it.
405
406
407 == 4.1 LoRaWAN Network  Server ~-~- The Things Network - Stack (TTN-V3) ==
408
409
410 You can access the gateway's built-in LNS server of (% style="color:blue" %)**The Things Network - Stack **(%%)via the URL( (% style="background-color:yellow" %)__**//http:~/~/<hostname>:8080 or http:~/~/<local-IPV4-address> //**__(%%)) in your browser.
411
412 Such as  (% style="background-color:yellow" %)__**//http:~/~/dragino-54ff12:8080  or http:~/~/<Local-IPV4-Address>//**__
413
414
415 Login account:
416
417 **User ID: ** ** (% style="background-color:yellow" %)admin(%%)**
418
419 **Password: ** ** (% style="background-color:yellow" %)dragino(%%)**
420
421
422 [[image:image-20220725171719-1.png||height="570" width="769"]]
423
424
425 == 4.2 Application Server ~-~- Node-Red ==
426
427
428 You can access the gateway's built-in AS server of (% style="color:blue" %)**Node-Red **(%%)via the URL((% style="background-color:yellow" %)__**//http:~/~/<hostname>:1880 or http:~/~/<local-IPV4-address>//**__(%%)) in your browser.
429
430
431 Such as (% style="background-color:yellow" %)__**//http:~/~/dragino-54ff12:1880  or http:~/~/<Local-IPV4-Address>//**__
432
433
434 [[image:image-20220725172124-3.png||height="610" width="843"]]
435
436
437
438 === **Using Node-Red, InfluxDB and Grafana** ===
439
440 The LPS8-V2 supports this combination, the default, Node-red is pre-installed but the InfluxDB and Grafana is not pre-installed.
441
442
443 the users can refer to this link to install them.
444
445 [[http:~~/~~/wiki.dragino.com/xwiki/bin/view/Main/Armbian%20OS%20instruction/#H2.6HowtoinstallGrafanaandinfluxdb>>http://wiki.dragino.com/xwiki/bin/view/Main/Armbian%20OS%20instruction/#H2.6HowtoinstallGrafanaandinfluxdb]]
446
447
448 = 5. How users can access LPS8v2 using serial USB =
449
450
451 (% style="color:blue" %)**USB TTL to LPS8v2  Connection:**
452
453
454 Port 1 of the UART on the LPS8v2 is GND
455
456 (% class="box infomessage" %)
457 (((
458 **TXD  <~-~--> UART RXD (Gray line)**
459
460 **RXD  <~-~--> UART TXD (White line)**
461
462 **GND <~-~--> GND (Black line)**
463 )))
464
465
466 **LPS8v2 UART connection photo**
467
468 [[image:image-20220804163015-1.png||height="621" width="466"]]
469
470
471 In the PC,you can use the serial port tool(such as [[putty>>url:http://www.chiark.greenend.org.uk/~~sgtatham/putty/download.html]] in Windows), you need to set the serial baud rate to (% style="color:blue" %)**115200**(%%) to access the serial console for LPS8v2. LPS8v2 will output system info once power on as below:
472
473
474 [[image:image-20220804164928-3.png||height="320" width="332"]]
475
476
477 [[image:image-20220804164747-2.png||height="622" width="594"]]
478
479
480 = 6. Use the helium gateway-rs as the Data-only Hotspot =
481
482
483 == **Step 1: Configure Frequency Band** ==
484
485
486 //Each country has a requirement for frequency region. Choose the right one for your area.//
487
488 [[image:image-20220905164308-1.png]]
489
490
491
492 == **Step 2: Configure the forward address** ==
493
494
495 **Select one of the servers to configure.**
496
497 **For example:**
498
499 [[image:image-20220905164847-2.png]]
500
501
502
503 == **Step 3: Download and Install the Helium-gateway-rs** ==
504
505
506 **Access the gateway CLI via SSH.**
507
508 [[image:image-20220905165222-3.png]]
509
510
511 **Download gateway-rs.**
512
513 [[image:image-20220905165715-5.png]]
514
515 (% class="box infomessage" %)
516 (((
517 **Command: wget [[http:~~/~~/repo.dragino.com/release/tool/gateway-rs/helium-gateway-v1.0.0-alpha.31-raspi234.deb>>http://repo.dragino.com/release/tool/gateway-rs/helium-gateway-v1.0.0-alpha.31-raspi234.deb]]**
518 )))
519
520
521 **Install gateway-rs.**
522
523 [[image:image-20220905165917-7.png]]
524
525 (% class="box infomessage" %)
526 (((
527 **Command: dpkg -i helium-gateway-v1.0.0-alpha.31-raspi234.deb **
528 )))
529
530
531 **Modify configuration.**
532
533
534 [[image:image-20220905173847-12.png]]
535
536
537 (% class="box infomessage" %)
538 (((
539 **region=<Enter regional parameters> \
540 && sed -i '/region/d' /etc/helium_gateway/settings.toml && sed -i "1 i\region = \"$region\"" /etc/helium_gateway/settings.toml \
541 && sed -i '/region/d' /etc/helium_gateway/default.toml && sed -i "22 i\region = \"$region\"" /etc/helium_gateway/default.toml**
542 )))
543
544
545 **Restart the helium_gateway**
546
547 [[image:image-20220905170920-9.png]]
548
549
550 (% class="box infomessage" %)
551 (((
552 **systemctl restart helium_gateway**
553 )))
554
555
556 **Check the helium_gateway Log：**
557
558 [[image:image-20220905173952-13.png]]
559
560
561 (% class="box infomessage" %)
562 (((
563 **journalctl -u helium_gateway -f**
564 )))
565
566
567 (% style="color:red" %)**Note: if your device is not finished the onboarding, which is unable to connect to the Helium console.**
568
569 where the helium gateway log is shown:
570
571 [[image:image-20220905174534-14.png]]
572
573
574 So you have to finish the onboarding, ~-~--Please refer to [[Step 2.7>>doc:Main.Notes for Helium.WebHome||anchor="H2.7A0Step6:OnboardingData-OnlyHotspot"]] to onboarding your LPS8-V2.
575
576
577 = 7. OTA System Update =
578
579
580 LPS8v2 supports system auto update via OTA, please see **[[this URL>>url:http://wiki.dragino.com/xwiki/bin/view/OTA%20Update/]]** for the detail of this feature.
581
582
583 = 8. Trouble Shooting =
584
585 == 8.1  I can't log in to the built-in Server TTN Stack which shows '**Login failed**'. ==
586
587
588 [[image:image-20220920135918-1.png]]
589
590
591 This is caused by the inconsistency between the built-in TTN-Stack domain configuration and your login URL.
592
593 By default, ttn-stack uses the gateway's domain name for URL resolution, but in some networks, they prefer to resolve IP-v4 addresses.
594
595
596 So you can change the domain name of the TTN-Stack configuration to the IPv4 address.
597
598 **Click the update URL button to configure the URL with the current eth port address.**
599
600 [[image:image-20220920141936-2.png]]
601
602
603 = (% style="color:inherit; font-family:inherit; font-size:29px" %)9. Supports(%%) =
604
605
606 (((
607 **//If you are experiencing issues and can't solve them, you can send mail to [[support@dragino.com>>mailto:support@dragino.com]].//**
608 )))
609
610 (((
611 **//With your question as detailed as possible. We will reply and help you in the shortest.//**
612
613
614 = 10. Reference =
615
616
617 * Install Tago Core: Refer **Install Tago Core in LPS8v2** in[[ Instruction>>doc:Main.Tago\.IO.WebHome]].
618 * [[Advance OS Reference Guide for LPS8v2>>doc:Main.Armbian OS instruction.WebHome]].
619
620
621 )))
622
623 = 11. Order Info =
624
625
626 (% style="color:#0000ff" %)**LPS8v2-XXX-YYY**
627
628 (% style="color:#0000ff" %)**XXX**(% style="color:black" %): Frequency Band
629
630 * (% style="color:red" %)**AS923**(%%): LoRaWAN AS923 band
631 * (% style="color:red" %)**AU915**(%%): LoRaWAN AU915 band
632 * (% style="color:red" %)**EU868**(%%): LoRaWAN EU868 band
633 * (% style="color:red" %)**KR920**(%%): LoRaWAN KR920 band
634 * (% style="color:red" %)**US915**(%%): LoRaWAN US915 band
635 * (% style="color:red" %)**IN865**(%%):  LoRaWAN IN865 band
636
637 (% style="color:#0000ff" %)**YYY**(% style="color:black" %): 4G Cellular Option
638
639 * (% style="color:red" %)**E**(%%):  EMEA, Korea, Thailand, India.
640 * (% style="color:red" %)**A**(%%):  North America/ Rogers/AT&T/T-Mobile.
641 * (% style="color:red" %)**AU**(%%): Latin America, New Zeland, Taiwan
642 * (% style="color:red" %)**J**(%%):  Japan, DOCOMO/SoftBank/ KDDI
643
644 More info about valid bands, please see [[EC25-E product page>>url:https://www.quectel.com/product/ec25.htm]].
645
646
647 = 12. Manufacturer Info =
648
649
650 **Shenzhen Dragino Technology Development co. LTD**
651
652 Room 202, Block B, BCT Incubation Bases (BaoChengTai),  No.8 CaiYunRoad
653
654 LongCheng Street, LongGang District ; Shenzhen 518116,China
655
656
657 = 13. FCC Warning =
658
659
660 (((
661 This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
662 )))
663
664 (((
665 ~-~- Reorient or relocate the receiving antenna.
666 )))
667
668 (((
669 ~-~- Increase the separation between the equipment and receiver.
670 )))
671
672 (((
673 ~-~- Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
674 )))
675
676 (((
677 ~-~- Consult the dealer or an experienced radio/TV technician for help.
678 )))
679
680
681 (((
682 Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.
683 )))
684
685
686 (((
687 The antenna(s) used for this transmitter must be installed to provide a separation distance of at least 20 cm from all persons and must not be co-located or operating in conjunction with any other antenna or transmitter.
688
689
690 )))
691 )))