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Reviews For: DCI VHF Filters

Category: Filters, RF: bandpass, duplexer, lowpass, highpass, RFI/EMI

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Review Summary For : DCI VHF Filters
Reviews: 19MSRP: CALL
General purpose filters used for reducing intermod.
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
W0FEN Rating: 2018-03-07
FANTASTIC!! Time Owned: more than 12 months.
I lived about a half mile from a IMTS VHF mobile telephone transmitter. The Motorola design was cheap. It had high-pass and low-pass to isolate the transmitter from the receiver. They called it diplexer. The result was it wiped out 2 Meters for me. This filter COMPLETELY ELIMINATED the interference. I would buy one of their filters IN A HEARTBEAT, if needed.
G7UTB Rating: 2017-10-03
Forgot how good they are Time Owned: more than 12 months.
I have just moved my shack into a bigger room. Connected all new cabling patch leads etc and switched on the 2m multi-mode. Inter-mod across the band! I had left the DCI filter forgotten behind the old desk. Patched it in line and all quiet again. I had forgotten how effective it had worked for the last 20 years or so. Looking at communication tower 120m away I thought what a great investment the filter was.

AB5Q Rating: 2012-09-09
Excellent Filters Time Owned: more than 12 months.
Living in an area 20 miles line-of-sight west of a multi-megawatt RF curtain of VHF/UHF transmitters, even the most robust receiver front end needs help with weak signal reception. Over the past several years I've purchased used DCI bandpass filters for VHF/UHF to help improve my receiver’s S/N ratio looking east. As a secondary benefit, the filters also protect sensitive GaAsFET and PHEMT receiver front end circuitry from strong out of band signals radiating from nearby antennas. The filters also provide a means to shunt the receiver’s front end to < 0.1-ohm above dc ground potential. The filters have easily reduce my noise floor looking east by 3-6 S-units resulting in an MDS of < -100 dB in most cases. Typical random, continuously shifting, intermodulation distortion has transitioned from s9+20dB levels to a state of non-existence. The filters work as anticipated however the customer service/direct order processing is broken but that’s a subject for another forum.

One final note, the $119.00 MSRP listed in this particular review is a bit out of date. These filters now cost between $400-500 new, and from $250-300 on the used market.
WY3X Rating: 2011-07-17
Works like a champ! Time Owned: more than 12 months.
KT6KT, hopefully 435~450MHz is not in the passband of your 2M radio! If it is, you might want to replace the radio, not the bandpass filter! I find it eliminates VHF-HiBand paging interference at my location on 2M, where my primary objective is 2M SSB near 144.200. I got mine for a bargain price, and it works great! The spec sheet doesn't go up as high as 435MHz, so you can't really say they misrepresented it. It's mostly for notching out VHF-HiBand interference. Perhaps you bought a boat intending to drive it on the highway...?
KT6KT Rating: 2011-07-16
More BAD News Time Owned: more than 12 months.
The attenuation of a DCI-145-2H filter between 435 and 450 MHz is less than 10 dB.
Photo available on request.
VE2DC Rating: 2010-01-31
Very effective. Time Owned: more than 12 months.
Ever since they started making Amateur VHF/UHF gear double as scanners (a dreadful idea in my opinion) many radios are horribly prone to intermod. This provides the necessary selectivity.
GM1SXX Rating: 2006-02-11
Superb intermod killer Time Owned: more than 12 months.
DCI 144-146Mhz (UK) 4 chamber VHF filter.

I have one of the 4 chamber VHF filters.

I live in a large town (pop. 85,000)and pager breakthrough was a perennial problem. The 2M band was very noisy until I bought this filter. I now know that 2M is not so bad after all, in fact its actually very good.

All of the problems I had have completely disappeared showing that poor design of the front ends in my radios was to blame.

If you live in a high RF environment I can thoroughly recommend these filters. They are very well made... yes I did do the unforgiveable and carefully took mine apart for a look, although I really don't recommend this. Mine was second-hand so it wasn't such a big deal.

The filter is built from four pieces of square section alumin(i)um extrusions screwed to solid brass top and bottom plates with machined coupling slots between the chambers. The resonators appear to be made of central-heating copper microbore tube and are self-supporting with additional foam tubes tucked in between the edges of the cavities and the resonators for additional support. The earthy ends of the resonators are flattened and soldered directly to the brass baseplate making for a strong and rigid assembly. No capacitors are used in this filter and it has no adjustments, having been factory aligned.

Build quality and performance is superb. Insertion loss is very low indeed. Sweeping the filter using my HP141T SA & HP8444A tracking generator confirms the excellent performance.

These are very fine filters indeed.
I have to give this filter a 5 on all counts.
It is one of my better purchases over the years.

73 Al.
KC4PX Rating: 2004-07-08
K4T DXpedition with excellent results Time Owned: 0 to 3 months.
The K4T DXpedition team (Dry Tortugas) was fortunate to use DCI VHF Bandpass Filters on 2 meters and 6 meters. We had two stations running in the same tent, one on HF, the other on 6 and 2 meters. Both filters were the 4 pole type capable of handling 200 watts. Our first impression was how massive these filters were and very well made. As for operation, we never had a problem. Each station operated without any interference throughout the 4 days on the island. On the HF station, we utilized Array Solutions Bandpass Filters for 20, 40 & 80 meters. When considering a multi-op DXpedition or contest operation, having Bandpass filters on each band is a must, otherwise significant interference and operator annoyance would limit the efficiency and tolerance of each operator. I highly recommend these Bandpass Filters to anyone serious on weak signal and contest operation.
N1OFJ Rating: 2003-12-10
very pleased Time Owned: 0 to 3 months.
Purchased a UHF custom rackmounted unit for use as a window filter for a 8 channel receive multicoupler (amateur use). Works as advertised with low insertion loss (confirmed with test eq). Nice steep skirt at band edges. Very pleasant people to deal with. Great bang for the buck. Will consider purchasing other products from DCI for future projects.

Dave N1OFJ
WB9PNU Rating: 2003-07-08
Worth every dollar Time Owned: 0 to 3 months.
I am using an Icom 207H duo-bander in my Jeep.
I was experiencing lots of interference from intermod products, pagers, and other sources of rf. In some areas around St. Louis, MO it was almost impossible to hear even the repeaters. Now all is well. I just installed the dual band DCI bandpass filter a few days ago. Wow! What a difference. I haven't heard anything but other hams since installed. DCI filter is very massive, heavy, precision made filter. Worth every dollar I paid for it.