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Reviews For: PAR SCANNER INTERMOD FILTERS

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

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Review Summary For : PAR SCANNER INTERMOD FILTERS
Reviews: 41MSRP: 74 USD
Description:
These scanner filters are used to eliminate interference from high powered pagers and channel "skipping" from other frequencies. The filters are designed to eliminate specific offending frequencies.
Product is in production
More Info: http://www.parelectronics.com/scanner.php
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00415
KC1UA Rating: 2015-02-06
Worth EVERY penny! Time Owned: 0 to 3 months.
About five minutes into VHFSYM152HT post-install monitoring, I knew the money I sent Dale was well spent. My filter is placed on the input side of a Stridsberg MCA204M multicoupler sharing a Comet GP-15 antenna that is exclusively used for receive only in the VHF and UHF public safety ranges. Suffice to say this filter is kicking the offending paging system's butt! I was getting killed by a strong paging system on 152.600 which was mixing with a local NOAA weather broadcast at 162.550 and dumping out in the 165-170 MHz range on my Uniden BCD996XT. I enjoy unattended searching, logging, and audio recording using ProScan software in that band for signals and prior to this filter it was nearly impossible to do so. Problem solved! Also, looking at the signal via my Airspy SDR it is clearly significantly attenuated, no more images and aliases from it showing up on screen. Without the filter the signal peaked right at around 0 db, with the filter inline it was knocked down to the area of -40 db as advertised, and any aliases or images from it that appeared all over the FFT were gone.

I'm not sure what delayed me in buying one of these gems, but I am certainly glad I did. As mentioned elsewhere in these reviews, communication with Dale is a pleasure; questions are promptly answered in a knowledgeable and friendly manner. I have bought other items from Dale in the past and this customer friendly approach is always consistent.

I'm extremely pleased and I would not hesitate to recommend this filter to anyone having a similar problem. Talk about $$ well spent!
JOHNNYMA75 Rating: 2015-01-08
Product works great and good customer service Time Owned: 0 to 3 months.
The purchase of a VHFSYM162HT scanner filter was well worth the money. I live close to a NWS tower and my regency scanner was useless from 151Mhz to 160Mhz with 162.55Mhz on every frequency. The VHFSYM162HT filter works great!!! A 134.25 frequency was overloading my bearcat scanners and the image was on 155.85Mhz. I ordered a custom filter notched at 134.25Mhz and once again the product worked very well!!! Dale makes a high quality product that works and customer service is A+++.
KC7YRA Rating: 2014-11-11
Absolutely stunning product and customer service Time Owned: 0 to 3 months.
My review follows the many written before it.

Almost instantaneous email response, with an almost as quick diagnosis. We quickly determined that an existing Par filter design could be easily tweaked and fit my requirements.

I have a mobile digital scanner in my vehicle. Whenever I transmit on an adjacent VHF ham radio, it completely wipes out not only the VHF public safety stuff, but also the 800mhz digital traffic.

Par built me up a filter with the specific connectors I needed and shipped it out in a couple days.

I just got the filter and WOW!! What an excellent product. It comes in a well built enclosure perfect for the mobile environment.

I can now use the ham rig while using the scanner.

Excellent service and product.
WILL12943 Rating: 2014-03-28
152mhz and 158mhz Time Owned: 0 to 3 months.
Great Job over there at Par. My intermod is gone from 152.48mhz and 157.74 MHz perfect tuning and im able to receive in the 151-152 range and 153-156.5 range where I had nothing but intermod pager sounds.. Par tuned these right on the money...
I highly recommend both the VHFSYM152HT AND THE VHFSYM158HT... these have cut out 2 of my 3 offending frequencies completely... I will be buying their FM trap to kill out a local fm broadcast station for npr in the very near future.
Thanks also for the 20 or so emails back and forth with all the help.. Will recommend...
KCREDEYE Rating: 2013-12-10
PAR SCANNER INTERMOD FILTER Time Owned: 0 to 3 months.
After years of inactivity, I decided to dust off a couple old scanners, and plug them in. Not finding a lot of clear activity, I installed a Diamond Discone Antenna atop a pushup pole ( put it about 35 feet up); only to discover that my ole scanner was picking up a NOAA weather broadcast that is transmitting just a mile or so from me on almost every frequency I programmed. In attempting to determine the reason for this I turned to the internet.

It was within that research that I found Eham.net and the positive reviews on Dale Parfitt and his company, Par Electronics. Hoping I’d correctly identified my problem, I sent them and e-mail explaining it; to which I got a very prompt and polite reply indicating they could build a SCANNER INTERMOD FILTER that would likely remedy my problem. I ordered said filter, and within a few days received a very well built filter, that instantly solved my issue! I highly recommend this company and their products, and will certainly keep them in mind for any amateur radio/scanner needs in the future!
KD7HGK Rating: 2013-01-03
VHF SYM 162HT scanner filter Time Owned: 0 to 3 months.
I just got the filter a few minutes ago. It works wonders. I'm no longer hearing NOAA weather radio (I'm 4 miles from the kilowatt transmitter) in the aircraft band, 2 meter band, or the 150MHz public safety portion. THANK YOU!. 162.475 is attenuated very nicely, it's still quite readable on it's own frequency and it doesn't bleed over to 162.450 full strength (I have to turn my squelch all the way down now to hear it on .450) anymore. The filter is very well constructed and was packaged well. I ordered it on Sunday, December 30th, 2012 and received it today, 1/3/2013. Fast shipping. No issues with Paypal. I would definitely do business with W4OP and PAR Electronics in the future.

Sincerely,

Jonathan A. Smith, KD7HGK
F6DEX Rating: 2012-09-16
Well done Time Owned: 0 to 3 months.
I ordered this filter after a mitigate result just above 120MHz with an other brand. This filter is much better : less IMD or phase noise and more signal. + nice and solid built and certainly precisely tuned. Thank you !
HAMPSHIRE Rating: 2012-07-31
VHFTN152-156 U.K. Pager Filter Time Owned: 0 to 3 months.
I’ve had an interest in recording NOAA low resolution APT weather satellite images for a number of years now and results have steadily improved as my knowledge has increased.
Starting with a Uniden scanner, wideband antenna and WXtoImg software I now have a dedicated receiver, an R2ZX. Building homemade right hand circular polarized antennas has helped in the reduction of pager interference and other anomalies. The receiver has two RF input ports, 30KHz IF bandwidth and strong filtering to combat the Pager frequencies that plague the UK enthusiasts.
One of the main problems with this hobby is the requirement to record up to a fifteen minute transmission with as little noise or interference as possible in an urban family home. Any imperfections in the received signal will be evident in the resultant image. The software can certainly help reduce or clean the image but at the cost of image detail and duration.
Investigating the many sources of interference, I decided to look deeper into pager interference. I hooked up the Uniden scanner to one of the RHCP antennas and scanned 150-160 MHz range. It didn’t take long to identify the extremely strong frequencies and the variance of tones heard. I then compared these tones when listening to the NOAA satellites in the 137-138 MHz range. It was clear that the pager signals were completely swamping the satellite signal.
The filter in the R2ZX was just shy of rejecting the problem frequencies at my QTH, in my case 153.325 MHz. It is possible that the built-in filter was designed to cover a wider frequency range at the cost of lower rejection. So this is where I decided to make improvement.
The answer came from PAR Electronics in the form of a model VHFTN152-156 U.K. Pager Filter. Two weeks later the unit arrived and was fitted to the external mast mounted QFH Antenna. At this time I was very familiar with the current duration and image quality expected from my system and was very impressed with the improvement with the filter in line.
But the story does not end here. My receiver has two RF input ports, and with the diversity feature enabled, will sample each port in real time and record the best signal. The loft mounted RHCP Double Cross Antenna (DCA) was still an avenue for the pager interference to worm its way into the recording. Well you might never have guessed another filter was required. An email chat with an extremely helpful chap known as Dale ensued but this time round, the required pass band and targeted notch frequencies were detailed.
One week later, Dale had built the filter to my requirements and I was amazed at the tuning plot he achieved. The pass and rejection specifications were outstanding. I have never seen my system produce such pleasing results in both duration and clarity. Even the portions of the images where the satellite is low in altitude have greater detail and less noise. I would say that the pager problems have now cleared and time can be utilized on other improvements.
I would like to repeat thanks to Dale in this review, he builds a very professional, high quality products and the service he provides is outstanding. One very pleased customer here.

----------------------
Earlier 5-star review posted by HAMPSHIRE on 2012-07-31

I’ve had an interest in recording NOAA low resolution APT weather satellite images for a number of years now and results have steadily improved as my knowledge has increased.
Starting with a Uniden scanner, wideband antenna and WXtoImg software I now have a dedicated receiver, an R2ZX. Building homemade right hand circular polarized antennas has helped in the reduction of pager interference and other anomalies. The receiver has two RF input ports, 30KHz IF bandwidth and strong filtering to combat the Pager frequencies that plague the UK enthusiasts.
One of the main problems with this hobby is the requirement to record up to a fifteen minute transmission with as little noise or interference as possible in an urban family home. Any imperfections in the received signal will be evident in the resultant image. The software can certainly help reduce or clean the image but at the cost of image detail and duration.
Investigating the many sources of interference, I decided to look deeper into pager interference. I hooked up the Uniden scanner to one of the RHCP antennas and scanned 150-160 MHz range. It didn’t take long to identify the extremely strong frequencies and the variance of tones heard. I then compared these tones when listening to the NOAA satellites in the 137-138 MHz range. It was clear that the pager signals were completely swamping the satellite signal.
The filter in the R2ZX was just shy of rejecting the problem frequencies at my QTH, in my case 153.325 MHz. It is possible that the built-in filter was designed to cover a wider frequency range at the cost of lower rejection. So this is where I decided to make improvement.
The answer came from PAR Electronics in the form of a model VHFTN152-156 U.K. Pager Filter. Two weeks later the unit arrived and was fitted to the external mast mounted QFH Antenna. At this time I was very familiar with the current duration and image quality expected from my system and was very impressed with the improvement with the filter in line.
But the story does not end here. My receiver has two RF input ports, and with the diversity feature enabled, will sample each port in real time and record the best signal. The loft mounted RHCP Double Cross Antenna (DCA) was still an avenue for the pager interference to worm its way into the recording. Well you might never have guessed another filter was required. An email chat with an extremely helpful chap known as Dale ensued but this time round, the required pass band and targeted notch frequencies were detailed.
One week later, Dale had built the filter to my requirements and I was amazed at the tuning plot he achieved. The pass and rejection specifications were outstanding. I have never seen my system produce such pleasing results in both duration and clarity. Even the portions of the images where the satellite is low in altitude have greater detail and less noise. I would say that the pager problems have now cleared and time can be utilized on other improvements.
I would like to repeat thanks to Dale in this review, he builds a very professional, high quality products and the service he provides is outstanding. One very pleased customer here. www.abhinton.co.uk/Weather.html
KI4WBJ Rating: 2012-02-25
PAR FM Trap Filter A+++ Time Owned: 0 to 3 months.
Over the last few weeks I’ve gotten back into monitoring Mil and Civil Air. I have Uniden, GRE and Radio Shack Scanners in my collection. When scanning certain frequencies I started noticing certain active frequencies were stopping and I was getting what sounded like FM radio traffic. When I opened the squelch all the way I could clearly hear the music. I though this was kind of bizarre since I live in the county. Upon further investigation I discovered that there was a FM station (95.7) within 3 miles of my house with a very strong signal output.

I was currently using a Radio Shack FM Trap because I have a Pro-197 and everyone knows they suffer from front-end overloads and FM bands resulting in poor VHF air band monitoring. Since I run a Stridberg MCA208M Active Multicoupler I figured I move the FM trap over so it covered all my radios. Well the results were not what I expected. The 197’s were still able to monitor Air Bands but I was still getting hammered by 95.7 on all my radios.

I figured it was time for me to invest in a true VHF FM Trap and stop using a TV FM filter. Sure the RS filter does a great job but I needed something to help in my situation. Like many others I couldn’t decide between the HPN-30118 Combined Notch Filter (cheaper) or the PAR Electronics FM filter. Before I decided to go the cheaper route and order the 30118 I decided to send Dale @ PAR and email on what was going on and see what he suggested. I sent off an email around 2100hrs figuring I would probably hear back from Dale within 24hrs. To my surprise I heard back from him a few minute later. He made a few suggestions and sent me a schematic on how he could adjust one of his standard FM filters so the 95.7 FM could be eliminated. He even explained to me why the RS filter was not performing as a true filter would. We continued to chat back and forth and within 1 hour from the original email I placed my order with Dale. He was able to quickly answer my questions and said he could make the adjustments and send it off the next day. I was blown away by this news.

The next morning before I had time to finish up my second cup of coffee I received an email from Dale with an updated schematic on how my filter would be tuned along with a UPS tracking number. Now all this originally started on a Wednesday evening. By Friday afternoon I had my new FM filter in hand. You can’t be that for service.

If your wondering why I spent double the money for a PAR filter then re-read the first few paragraphs. Sure I could have gotten a standard HPN-30118 and it may have done the job fine but it’s a basic stock item. If it didn’t work the way I wanted then I would have to send it back for a refund. By purchasing with from Dale @ PAR Electronic I get the following:

- I have one-on-one communication
- Quality construction and design with connectors to meet my requirements
- Option to send filter in for repairs or adjustments as needed
- Non off-the-shelf item. Configured for my situation.

I could go on but you get the point. Dale provides a service you don’t see very often. Do yourself a favor and spend the few extra bucks. You can’t go wrong and the results are outstanding.
850MIKE Rating: 2012-01-17
SPOT-ON!! Time Owned: more than 12 months.
Combine the technical ability of this filter with the customer service of Par Electronics and you have a combination that is hard to find these days.

After having my Uniden scanner's front end on VHF get trashed by two nearby FM broadcast stations when connected to my rooftop discone, Dale Parfitt from Par Electronics was able to custom tune this filter for deep fades right on the offending frequencies! The difference was literally night and day. My distant aircraft signals began bounding in like I'd never heard them before.

Par Electronics was fast with getting the filter built, and sent to me, and the price was very reasonable.

Recently I have gotten into DSTAR amateur radio. I connected my DVAP dongle (which serves as a mini- low-power simplex repeater) to the discone to see what sort of "neighborhood" range I'd get out of my DVAP. I was thrilled to discover I could hear with the HT my DVAP easily 2 miles from my home QTH, despite very low TX power, but disappointed to find that the DVAP was essentially "deaf" due to the same RF overload that plagued my scanner. The noise floor would go from -110dBm to -90dBm when I connected the DVAP to the discone. I simply couldn't get back into my DVAP unless I was within a few blocks of the house. I remembered the custom filter from Par Electronics that I had. I emailed customer support late on a Friday to find out if it the device handle low TX power. I fully expected it'd be Monday before I had even the slightest chance of a reply. I heard from Dale within 45 minutes where he confirmed power <500mW should be ok to transmit through the filter so long as I check return loss/insertion loss on the TX frequency. I confirmed no problems transmitting through the filter and the PROBLEM WAS SOLVED! Noise floor improved by 10dB when using the filter (from around -90 to around -100). My DVAP began hearing me everywhere I could hear it!

I'm a fan!