Bandpass Filter for 2m
Designed and manufactured by SOTABEAMS, this neat bandpass filter is for use with handies (HT) in areas with multiple transmitters. In such areas, many HTs suffer from blocking. This is a ready-made unit - not a kit. Can be used either way round. Just connect between HT and antenna. Our filter is also perfect for use with SDR receivers which may suffer from blocking problems.
Filter power rating:
- FM/DATA 5 Watt max (30% duty cycle recommended, max continuous TX 90 seconds). 2 Watts continuous.
- SSB 5 Watts PEP max continuous.
Filter bandwidth 144 - 148 MHz
- In-band typically < 3dB
- 433 MHz > 70dB
- 155 MHz approx. 25dB
- FM broadcast band >70dB
- Air band > 50 dB
Temperature range 0 - 50 Centigrade
Weight 25 grams
Filter supplied in a bespoke plastic case (nylon)
Case includes guides for cable ties
45 x 20 x 18 mm (case)
Connectors SMA-female both ends.
Bright colours to make them harder to leave behind.
Also available from our agent(s):
5 Reviews Hide Reviews Show Reviews
I live within a mile of Olivers Mount a 7KW FM and Freeview TV mast. I bought this filter to test a theory that the mast was dragging down 2m reception at my home QTH. I had previously tried activating the transmitter site as a HEMA summit but failed due to RX swamping causing me to hear nothing. I took delivery of the filter on Saturday. On Sunday I hooked up a Baofeng UV9R and tuned into the mast FM broadcast frequency 95.5. On WFM the signal could be received with a wet finger on the antenna socket it was so strong. I put the 9R onto a loft mounted slim Jim and the signal was so strong as to be breaking through several hundred KHZ adjacent. I then put the filter inline and tried again. There was nothing! Not even when tuned to 95.5 could I hear a single thing. I determine by experimentation that the rejection of broadcast FM is very very good. I think dialled up GB3RW a local repeater about 15 miles away. This repeater is usually scratchy at my QTH despite being able to open it. With the filter inline the RX from the repeater was a full 2 S points up and now breaks my squelch! Although I got the filter for SOTA I can see it becoming a permanent addition to the shack setup to. Wonderful, well made and works!
Bought this for my handies, a couple of cheap Baofengs and a Yaesu FT-25. It screws straight on to the handie antenna socket and then an adapter (male to male) is required to refit the rubber duck. No sweat. Fits easily, is unobtrusive and works well. Recommended.
Wow! The new SOTABeams 2m filter is awesome! Tested it on Squawk Mountain today. This local peak is covered in communications towers. Previous Activations have been so frustrating! I realized Chasers could hear me, but I couldn't hear them! With the squelch open, S-8 noise without the Bandpass filter, and completely eliminated the noise with the filter installed. Well worth $60. Having it made the Activation so much more fun and way less frustrating!
This filter is amazing. I'd give it 10 out of 5 if I could. I just activated W7W/KG-116. It has several large FM broadcast towers. The whole area is RF soup. During my previous activation of this summit I struggled to to make the four contacts. Only close-in high-power stations were able to get through to me. This time I used the filter with a roll-up J-pole and was able to get 17 QSOs in short order including a summit-to-summit 100 km away. I highly recommend this product if you are using an HT anywhere near broadcast towers.
I took the 2 meter SOTAbeams Band pass filter up to ZL3/cb-822 to see if it met my expectations & here is my report on it.
ZL3/CB-822 is one of two sites in Chch that is reknown for RF soup due to the 3 paging/cell towers that adorn the summit. Most of us when using 2 meters move right down to the edge of the activation zone in an attempt to avoid it & then only using rubber ducky arials. Slim jims are out unless you have a decent radio & they don't always cut the mustard. Baofengs are definately out.
So... Because I wanted to put the filter through a tough test, I went unusually close to the towers (approx 50 meters). There is a fence line there for bungeeing the pole to (thankyou Chch City Council), & up went the slim jim about 5 meters.
I started off with the Yaesu FT 270 R & put the filter in line. I hadn't put an alert up. Instead I had e-mailed/text my fellow ZL3 activators & chasers as I wanted them to come on & ragchew amongst themselves whilst I monitered the reception & coming in as a breaker as needed.
Geoff, ZL3GA & Gavin, ZL3GAV quickly obliged & after the usual formalities they QSOed between themselves & me. There was practically no drop of audio. This amazed me as I was prepared to disconnect the slim jim & go rubber ducky but no. Not needed. Other chasers & activators came & went & I was not dissaponted with the reception.
Next step was to connect the FT-70D & work on fusion mode. I'm afraid to say I didn't get the same results. It was definately getting muted quite consistantley. Whether that was fusion or the 70D I can't comment. I do enjoy activating a summit on fusion. I didn't take a Baofeng for testing.
Overall I'd give it a 9 out of 10. They come with female sma plugs at each end so I needed a male to male adaptor for my Yaesu hand helds which take a male sma.
Available from SOTAbeams UK & I got it into the country for just a touch under NZ$90:00 including postage direct although I daresay if a few of you got together & ordered 2 or three or more at once & shared the postage costs it might be cheaper.
Others of you may be more inclined to home brew your own. That's up to you.
This wee item will be coming with me on all of my future activations especially if there's a hint of RF soup.