{"id":50761,"date":"2021-11-07T12:03:07","date_gmt":"2021-11-07T16:03:07","guid":{"rendered":"https:\/\/swling.com\/blog\/?p=50761"},"modified":"2021-11-07T12:03:07","modified_gmt":"2021-11-07T16:03:07","slug":"jock-reviews-the-bhi-compact-in-line-noise-eliminating-module","status":"publish","type":"post","link":"https:\/\/swling.com\/blog\/2021\/11\/jock-reviews-the-bhi-compact-in-line-noise-eliminating-module\/","title":{"rendered":"Jock reviews the BHI Compact In-Line Noise Eliminating Module"},"content":{"rendered":"

Many thanks to\u00a0SWLing Post<\/em>\u00a0contributor,\u00a0Jock Elliott<\/a>, who shares the following guest post:<\/strong><\/p>\n

\n

\"\"<\/a>The noise, the neighbor, and the box<\/h1>\n

By Jock Elliott, KB2GOM<\/strong><\/p>\n

Imagine the annual meeting of an international corporation called SWLing Inc. (or SWLing LTD). The CEO, looking splendid in his custom-tailored suit, is addressing the assembled multitudes. On the giant screen is an equation showing signal-to-noise ratio. The CEO aims his laser pointer at the word \u201csignal.\u201d We want ALL of this, he says. Then he points at the word \u201cnoise,\u201d and says, \u201cand NONE of this.\u201d<\/p>\n

Then he looks at the audience and says, \u201cGot it?\u201d And he walks off the stage.<\/p>\n

That, whether they want to admit it or not, is the mindset of every single SWL, international music fan, overseas program listener, and DXer. Period. They want as much signal as they can get, and as little noise as possible. That\u2019s what drives radioheads to buy amplified loops, to string long wires, to build towers and yagi antenna arrays, to lay out beverage antennas hundreds of feet long, and to build ferrite sleeve loop antennas . . . it\u2019s all about the signal to noise radio. More signal, less noise.<\/p>\n

And it was noise that was bothering me . . . a kind of hiss, hash, eggs-frying sound. It was that noise that prompted me to create the horizontal room loop<\/a> to try to boost the signal coming into my Grundig Satellit 800 over the noise normally received on the Satellit\u2019s whip antenna.<\/p>\n

And it worked; there was more signal on top of the noise . . . but that hiss, hash, whatever you want to call it, was still there. I could hit the attenuator, and some of the noise would go away, but it was still there. After a while, it was just plain tiring on the ears. Poking around the internet, the wisdom seemed to be that the source of the noise was likely electric\/electronic gear in my radio room. So I killed the power to everything in my radio room, powered the Satellit 800 off internal batteries, and the noise was still there.<\/p>\n

So I called my neighbor. He\u2019s (a) a really good neighbor, (b) a ham with a serious station, and (c) technically knowledgeable. I explain the problem. He says, \u201cMeet me outside.\u201d<\/p>\n

We meet between the yards, and he has a Sony 7600 portable shortwave radio in his hand. He switches it on. \u201cIs this the noise you\u2019re talking about?\u201d<\/p>\n

\u201cYup,\u201d I say. \u201cThat\u2019s the atmosphere,\u201d he says. Well, nuts.<\/p>\n

More poking around the internet reveals that an amplified receive-only magnetic loop antenna might be significantly quieter, and there are several manufacturers of them. I\u2019m thinking about one of those loops when I run across a review of a relatively inexpensive ham transceiver that is reported to be excellent at pulling difficult signals out of the noise because of the superior \u201cdigital signal processing\u201d (DSP) that is built into the transceiver.<\/p>\n

Digital signal processing . . . that sounds promising . . . after all, if you take a step back and think about it, there are two ways to improve signal-to-noise ratio. One way is to improve the signal with better antennas and the like. The other way is to reduce the noise, and one way to achieve that might be through digital signal processing.<\/p>\n

So, are there any companies that make external digital signal processors that could be used with an HF receiver? There are several, it turns out. Some of the units are large, studded with knobs and look complicated to operate, and almost all of the offerings require an external power supply.<\/p>\n

But I wanted something that could be easily transferred between receivers and might even be used with a portable receiver when I was doing my horizontal DXing in bed. A big box that requires an external power supply was going to be awkward, cumbersome, and inconvenient. And that\u2019s when I ran into a British company called BHI<\/a>. They make noise cancellation products, gizmos that use digital processing to remove noise from an audio signal. They serve amateur radio, commercial, marine, medical, and even covert surveillance markets.<\/p>\n

One of their products is the Compact In-line Noise Eliminating Module<\/a>. It can be run off AA batteries and isn\u2019t much bigger than a deck of cards (in fact, its footprint is almost exactly the same as my CCrane Skywave SSB). It has just two knobs and is easy to set up: you just plug it in between your HF receiver and your headphones or external speaker. It even comes with a cable to connect your receiver to the Noise Eliminating Module.<\/p>\n

I order one from DX Engineering<\/a> in Ohio. The cost, delivered to my door, including tax, is just over $260 American dollars<\/a>. It arrives two days later, just in time for the bands to be sizzling with noise (apparently) produced by a solar coronal mass ejection (CME). The amount of noise is brutal, about as bad as I have ever heard in decades of hamming and SWLing.<\/p>\n

\"\"<\/a><\/p>\n

Plugging the BHI in-line module into my Satellit 800 and clamping the headphones over my ears, I begin tuning the 20-meter ham band. Part way up the band, I run into a Canadian ham chatting with someone. His signal is barely above the noise and copyable, but the noise is really annoying. I punch the button for the BHI device, and . . . the noise disappears. Wow! I press the right-hand button (to bypass the BHI device), and the noise comes back full force.<\/p>\n

Quickly, I grab my Tecsun PL-880, extend the whip antenna, tune to the same frequency, and plug the BHI in-line module into the 880. The noise sounds even worse on the 880 (the Canadian ham is barely copyable), probably because of the shorter antenna. But when I engage the BHI device, the result is even more dramatic; a very pleasant signal emerges as the BHI unit suppresses the noise, with just a bare hint of hiss still audible.<\/p>\n

Then I take hold of my CCrane Skywave SSB to see how the BHI in-line module will behave with that. It doesn\u2019t take long to realize that, apparently because of the solar activity, all the bands are noisy on the Skywave. Not just shortwave, but AM, FM, weather, and Air were all uncharacteristically affected by hiss or noise. The BHI Compact In-line Noise Eliminating Module reduced the noise and made each of them more pleasant to listen to, without exception. I am \u201cofficially\u201d impressed.<\/p>\n

As I experiment with the BHI device in following days, during which atmospheric conditions improve, I continue to be impressed. Why? Because the BHI Compact In-line Noise Eliminating Module is effective at substantially reducing noise without a lot of fuss and bother.<\/p>\n

As good as the BHI module is, though, it is not a miracle device; it does have some limitations. Sometimes it will not eliminate all the noise, even though the noise will be reduced substantially. If you crank up the level of filtering\/noise cancellation too high, it can distort speech and make tuning single sideband difficult. Further, you sometimes hear artifacts of the digital signal processing. These artifacts sound to me like trickling water, and, frankly, I don\u2019t find these sounds objectionable (they sure beat the heck out of the atmospheric noise), but some people, I suppose, might not like them.<\/p>\n

\"\"<\/a>

Image via DX Engineering<\/p><\/div>\n

The module is easy to operate. There are two knobs. Press the left one in to power up the unit, then turn the knob to adjust the volume. Press the right knob to activate noise reduction and then turn the knob to adjust the level of noise reduction. Sometimes, I find, the sweet spot for listening is with the noise substantially reduced \u2013 perhaps 85-90 percent \u2013 but not completely gone. Press the right knob again to bypass noise reduction and hear what the signal sounds like without the BHI module online.<\/p>\n

Because the two knobs on the face of the BHI module are also push-buttons, if you are going to pack the device in your luggage, remove the batteries to prevent the unit from inadvertently turning on and draining the batteries.<\/p>\n

Bottom line<\/strong><\/h1>\n

The BHI Compact In-line Noise Eliminating Module is highly effective at reducing or eliminating noise. It works on international broadcasters, ham single-sideband signals, and utility stations, as well as AM, FM, and even NOAA weather radio when conditions are horrible. It can make weak signals easier to hear and strong signals more pleasant for long-term listening. It reduces audio fatigue. It is not a cure-all for all signal-to-noise or audio problems, but it is a big help. Further, it can be readily moved from location to location and from radio to radio and adds a new capability to receivers that do not have built-in digital signal processing.<\/p>\n

I think it is a worthwhile addition to any shortwave listening post.<\/p>\n","protected":false},"excerpt":{"rendered":"

Many thanks to\u00a0SWLing Post\u00a0contributor,\u00a0Jock Elliott, who shares the following guest post: The noise, the neighbor, and the box By Jock Elliott, KB2GOM Imagine the annual meeting of an international corporation called SWLing Inc. (or SWLing LTD). The CEO, looking splendid in his custom-tailored suit, is addressing the assembled multitudes. On the giant screen is an […]<\/p>\n","protected":false},"author":15,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[4199,545,3,129,43],"tags":[5352,9527,4302,9323],"class_list":["post-50761","post","type-post","status-publish","format-standard","hentry","category-accessories","category-ham-radio","category-news","category-reviews","category-shortwave-radio","tag-bhi","tag-bhi-compact-in-line-noise-eliminating-module-review","tag-bhi-compact-in-line-noise-elimination-module","tag-jock-elliott-kb2gom"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pn3uc-dcJ","jetpack-related-posts":[{"id":54404,"url":"https:\/\/swling.com\/blog\/2022\/10\/sometimes-the-right-tools-lead-to-agreeable-results\/","url_meta":{"origin":50761,"position":0},"title":"Sometimes the right tools lead to agreeable results","author":"Jock Elliott","date":"October 23, 2022","format":false,"excerpt":"By Jock Elliott, KB2GOM Listening to the HF ham bands can be a lot of fun. All you need is a shortwave receiver capable of receiving single sideband (SSB) transmissions and a chart of the amateur bands. You can find downloadable PDF charts of the United States Amateur Radio Band\u2026","rel":"","context":"In "Antennas"","block_context":{"text":"Antennas","link":"https:\/\/swling.com\/blog\/category\/antennas\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2022\/10\/bhi-shortwave-001-1024x768.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2022\/10\/bhi-shortwave-001-1024x768.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2022\/10\/bhi-shortwave-001-1024x768.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":55033,"url":"https:\/\/swling.com\/blog\/2022\/12\/checking-out-the-xiegu-gnr1-digital-audio-noise-filter\/","url_meta":{"origin":50761,"position":1},"title":"Checking out the Xiegu GNR1 Digital Audio Noise Filter","author":"Jock Elliott","date":"December 14, 2022","format":false,"excerpt":"By Jock Elliott, KB2GOM Call me a retro-crank, an old-schooler, but part of the joy of listening to shortwave is that the signals sound like they have come from far away. There is nothing like hearing the music, the news, the commentary \u201cfiltered through the shortwaves\u201d . . . as\u2026","rel":"","context":"In "Accessories"","block_context":{"text":"Accessories","link":"https:\/\/swling.com\/blog\/category\/accessories\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2022\/12\/Xiegu-dsp-back-001.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2022\/12\/Xiegu-dsp-back-001.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2022\/12\/Xiegu-dsp-back-001.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2022\/12\/Xiegu-dsp-back-001.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":58319,"url":"https:\/\/swling.com\/blog\/2023\/12\/checking-out-some-headphones-for-dxing\/","url_meta":{"origin":50761,"position":2},"title":"Checking out BHI’s HP-1 and NCH headphones for DXing","author":"Jock Elliott","date":"December 3, 2023","format":false,"excerpt":"By Jock Elliott, KB2GOM As an oldster with a bit of hearing deficit, I am a big fan of anything that helps me to hear better when I am trying to tease out hard-to-hear signals, whether medium wave broadcast, shortwave broadcast, or single-sideband signals on the HF ham bands. Toward\u2026","rel":"","context":"In "Accessories"","block_context":{"text":"Accessories","link":"https:\/\/swling.com\/blog\/category\/accessories\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2023\/11\/hp-1-wired-stereo-headphones.1-ece10a7e.webp?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2023\/11\/hp-1-wired-stereo-headphones.1-ece10a7e.webp?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2023\/11\/hp-1-wired-stereo-headphones.1-ece10a7e.webp?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":50891,"url":"https:\/\/swling.com\/blog\/2021\/11\/jock-explores-the-essential-listening-post\/","url_meta":{"origin":50761,"position":3},"title":"Jock explores “The Essential Listening Post”","author":"Thomas","date":"November 17, 2021","format":false,"excerpt":"Many thanks to\u00a0SWLing Post\u00a0contributor,\u00a0Jock Elliott, who shares the following guest post: The Essential Listening Post By Jock Elliott, KB2GOM Listening to shortwave radio (or any radio, for that matter) is just plain fun. So what do you need to get in on the fun? A radio. With today\u2019s crop of\u2026","rel":"","context":"In "Accessories"","block_context":{"text":"Accessories","link":"https:\/\/swling.com\/blog\/category\/accessories\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2021\/11\/G12-SWLing-accessories-001-002.jpeg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2021\/11\/G12-SWLing-accessories-001-002.jpeg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2021\/11\/G12-SWLing-accessories-001-002.jpeg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2021\/11\/G12-SWLing-accessories-001-002.jpeg?resize=700%2C400&ssl=1 2x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2021\/11\/G12-SWLing-accessories-001-002.jpeg?resize=1050%2C600&ssl=1 3x"},"classes":[]},{"id":21253,"url":"https:\/\/swling.com\/blog\/2016\/09\/phil-demonstrates-the-bhi-neim1031-noise-eliminating-in-line-module\/","url_meta":{"origin":50761,"position":4},"title":"Phil demonstrates the BHI NEIM1031 Noise Eliminating In-Line Module","author":"Thomas","date":"September 8, 2016","format":false,"excerpt":"Many thanks to SWLing Post contributor, Phil Brennan, who writes: [Recently]\u00a0one of your contributors mentioned that he purchased a BHI DSP unit at a discounted price. I purchased one (a different model to the one in the previous post) some months ago before I headed away travelling. The post reminded\u2026","rel":"","context":"In "Accessories"","block_context":{"text":"Accessories","link":"https:\/\/swling.com\/blog\/category\/accessories\/"},"img":{"alt_text":"bhi-dsp","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/09\/BHI-DSP.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/09\/BHI-DSP.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/09\/BHI-DSP.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/09\/BHI-DSP.jpg?resize=700%2C400 2x"},"classes":[]},{"id":52181,"url":"https:\/\/swling.com\/blog\/2022\/03\/its-magic-but-its-real-the-joys-of-listening-to-the-ham-bands\/","url_meta":{"origin":50761,"position":5},"title":"“It\u2019s magic, but it\u2019s real”: The joys of listening to the ham bands","author":"Thomas","date":"March 13, 2022","format":false,"excerpt":"Many thanks to\u00a0SWLing Post\u00a0contributor,\u00a0Jock Elliott, who shares the following guest post: The joys of listening to the ham bands By Jock Elliott, KB2GOM \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u201cIt\u2019s magic, but it\u2019s real.\u201d That statement was uttered recently by an amateur radio operator \u2013 a ham \u2013 from South Carolina. 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