In Miri and Labuan, there are several radio stations using same frequencies with Brunei, causing co-channel interference.
==Miri vs. Brunei==
90.7MHz: RTM Red FM Bukit Lambir (Miri)
90.7MHz: Kristal FM Brunei Bukit Subok (Bandar Seri Begawan)
93.3MHz: Cats FM Bukit Lambir (Miri)
93.3MHz: RTB Nur Islam Brunei Bukit Subok (Bandar Seri Begawan)
Co-channel interference occurs in Tutong, but affected radio stations have alternative frequencies in co-channel interference areas by following below:
1. Cats FM: 88.7MHz Bukit Mas (Limbang)
2. Red FM: 104.1MHz Bukit Mas (Limbang)
3. Kristal FM: 98.7MHz Andulau
4. RTB Nur Islam FM: 94.9MHz Andulau
==Labuan vs. Brunei==
92.3MHz: RTM Ai FM Bukit Timbalai (Labuan)
92.3MHz: RTB Nasional FM Brunei Bukit Subok (Bandar Seri Begawan)
93.3MHz: RTM Sabah VFM Bukit Timbalai (Labuan)
93.3MHz: RTB Nur Islam FM Brunei Bukit Subok (Bandar Seri Begawan)
Bukit Timbalai doesn't overspill signal to Brunei, so RTB Nasional FM 92.3MHz and Nur Islam FM 93.3MHz are not interfered in Brunei, meanwhile Ai FM and Sabah VFM are having co-channel interference in Labuan Island, but Ai FM and Sabah VFM have alternative frequencies in Labuan when both are interfering with Brunei radio stations due to same frequencies.
When I searched Brunei radio stations reception in Sarawak on YouTube, the the search showed the recommended videos which I'm interested about, then I spotted there was a radio reception video of RTM Traxx FM 90.7MHz tuned in Tacloban, Philippines which published by HiRadSpek23 on 10th June 2023.
The FM 90.7MHz was Traxx FM signal from Lawa Mandau, Kota Kinabalu, Sabah actually, but the signal tuned in Tacloban, Philippines was Sporadic E propagation.
The transmitter power of Traxx FM 90.7MHz in Kota Kinabalu, Sabah, Malaysia (Lawa Mandau) is 1kW.
The signal was clear for a while, then it went weak and had co-channel interference with other radio station, the receiving distance was 1123km from Lawa Mandau to Tacloban.
Alongside Traxx FM 90.7MHz, HiRadSpek23 also tuned few radio stations from Sarawak (Malaysia) and Brunei in Tacloban, Philippines which were also Sporadic E propagation.
1. Cats FM 88.7MHz Limbang, Sarawak, Malaysia (Tx: Bukit Mas)
Distance: 1312km
2. Kristal FM 90.7MHz Bandar Seri Begawan, Brunei (Tx: Bukit Subok)
5 years ago, I went to Lawas, Sarawak for Cats FM transmitter system commissioning project as a junior broadcast engineer which is now a former career to me. When I was staying at a hotel in Lawas, Sarawak, I managed to tune Sabah VFM 102.9MHz, the signal was still clear there.
While Sabah VFM can be tuned via 102.9MHz clearly in Lawas, Sarawak, but I'm very curious whether it can be tuned in Limbang on same frequency or not like what I listened to Lawas, Sarawak. As today, I don't have opportunity to travel to Limbang yet due to the schedule plan, so I have two different method to identify the coverage availability such as plotting simulated coverage map and ask Limbang community, despite I have not obtained the video as better and stronger evidence.
Method 1: Plotting coverage map by using Nautel RF Toolkit
I plotted the coverage map of Sabah VFM 102.9MHz Bukit Tampalagus transmitter on Nautel RF Toolkit by entering its estimated radio transmission system parameters, but the simulated coverage map is not fully accurate because of the transmitter site measurement is not exactly correct.
From the coverage map above, there is no signal of Sabah VFM 102.9MHz if the listeners tune in Limbang town center due to terrain, meanwhile Sabah VFM 102.9MHz can be tuned from Sebukang to Pandaruan which is located behind Limbang town, but signal is varied, it can be either clear or weak. Alongside Limbang town, Sabah VFM 102.9MHz cannot be tuned in west side of Limbang district such as Batu Danau and Nanga Medamit.
Method 2: Get more information from Limbang community via social media
I approached Discover Limbang via Facebook by sending the enquiry for verification few days ago with following chats below:
Me: Hi, Discover Limbang. Commonly in Limbang, the listeners can tune Cats FM, RTM radio stations from Bukit Mas and Brunei radio stations, I would like to ask whether Sabah VFM 102.9 can be tuned in Limbang or not? Can you personally send me privately a video of tuning Sabah VFM 102.9 in Limbang (40 seconds video format)?
(Made first attempt to request sending the radio reception video of Sabah VFM 102.9MHz in Limbang, but I failed to get it yet)
Discover Limbang: Hi, Philip. Sabah VFM 102.9MHz cannot reach Limbang.
Me: Empty frequency (I meant the 102.9)
(Failed again to make 2nd attempt by requesting 30 seconds Sabah VFM 102.9MHz radio reception video in Limbang)
Discover Limbang: It can be only tuned via Astro Channel 870, not through the radio.
Me: For Sabah FM 97.9MHz (Bukit Tampalagus), feel that it has interference from Nasional FM 98.1MHz Bukit Mas transmitter.
Me: Thank you. Actually I would like to do Limbang radio DXing content(to target Sabah people who visits Limbang or has transit in Limbang before entering Miri or Brunei).Before making content, I would like to obtain more information from Limbang community(never jump to the conclusion without evidence).
Discover Limbang: Until today, Sabah radio stations cannot reach Limbang, except Astro (Sabah VFM).
==RESULTS==
By combining two methods, Sabah VFM cannot be tuned via Bukit Tampalagus transmitter on the frequency 102.9MHz in Limbang town center. In Limbang district, Sabah VFM 102.9MHz is only available in Pandaruan areas where are not far from Bangar, Brunei.
The result of Nautel RF Toolkit coverage map and answer from Discover Limbang are positively matched where both mentioned that Sabah VFM 102.9MHz cannot be tuned in Limbang, Sarawak.
By looking again the simulated coverage map, Sabah VFM 102.9MHz is only available in small part of Limbang, Sarawak, but the clear coverage of Sabah VFM 102.9MHz in Limbang is not located at the town center, instead the road near Brunei's Temburong border.
Although it is not possible to tune that radio station in Limbang due to terrains, but to make the radio reception video of Sabah VFM 102.9MHz in Limbang via on-site DXing, I need to wait until 2026 due to schedule availability plan.
In Limbang town, there has no Sabah's ethnics such as Dusun, Murut, Kadazan and Bajau, but my main target group of making Sabah VFM 102.9MHz radio signal in Limbang is transit users and Brunei people who come to Limbang, locally I can target Limbang's Chinese and Malay people if they tune Sabah VFM's Chinese and English programs via FM 102.9MHz from 9am to 3pm, alternative to Red FM 104.1MHz, Ai FM 103.3MHz and Traxx FM 102.3MHz.
Limbang is dominated by Malay, Iban, Chinese, Lun Bawang and Bisaya.
==Conclusion of Sabah VFM availabity in Sarawak==
Lawas District is the only clear coverage of Sabah VFM in Sarawak region via Bukit Tampalagus transmitter on 102.9MHz, Lawas District covers Lawas, Sundar, Trusan and Merapok.
(THROWBACK: 5 years anniversary of Sabah VFM 102.9MHz radio reception in Lawas, Sarawak)
Here are the videos of tuning Bernama Radio FM 107.5MHz Gunung Pulai signal in Batu Pahat District, Johor where I conducted on 27th October 2024.
1. Parit Sulong (84km)
2. Batu Pahat (74km)
3. Senggarang (57km)
Among 3 locations above, Bernama Radio FM 107.5MHz is very weak and having rough audio actually, but Rengit is the only clearest coverage of Bernama Radio FM 107.5MHz in Batu Pahat District, Johor.
In Batu Pahat District, Bernama Radio FM 107.5MHz Gunung Pulai signal is extremely weak in:
* Batu Pahat
* Senggarang
* Ayer Hitam
* Parit Raja
* Seri Gading
* Yong Peng
* Parit Sulong
* Parit Yaani
No signal can be tuned in Semerah and Sri Medan, Johor.
