{"id":61594,"date":"2025-01-11T08:34:32","date_gmt":"2025-01-11T12:34:32","guid":{"rendered":"https:\/\/swling.com\/blog\/?p=61594"},"modified":"2025-01-11T14:12:31","modified_gmt":"2025-01-11T18:12:31","slug":"hf-signal-enhancer-for-sdr-a-hands-on-build-by-steve-allen-kz4tn","status":"publish","type":"post","link":"https:\/\/swling.com\/blog\/2025\/01\/hf-signal-enhancer-for-sdr-a-hands-on-build-by-steve-allen-kz4tn\/","title":{"rendered":"HF Signal Enhancer for SDR: A Hands-On Build by Steve Allen (KZ4TN)"},"content":{"rendered":"

Many thanks to SWLing Post<\/em> contributor Steve Allen (KZ4TN)<\/a>, who shares the following guest post:<\/strong><\/p>\n

\n

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

SDR Signal Enhancer<\/b><\/h1>\n

by Steve Allen<\/strong><\/p>\n

I came across this HF Signal Enhancer for SDR on the RTL-SDR.com website. It was designed and built by Peter Parker, VK3YE from Melbourne, Australia. Below is the link to the video of the signal enhancer in action using an RTL-SDR V4 Software Designed Radio;<\/p>\n

www.youtube.com\/watch?v=W6OXc_wZTXU<\/a><\/p>\n

It was very easy to see and listen to the improvement to the signal reception the signal enhancer made. Having been a life-long shortwave listener and current SDR user, I had to build one.<\/p>\n

I did a screen capture of the schematic, re-drew it using MS Word, and built the bill of materials. In Peter\u2019s original design he included a T-R relay so you could use the SDR along with a transmitter, which I opted to leave out. I had the passive components in my \u201cjunk box\u201d but had to source the enclosure, controls, and antenna connectors. I have used these clam shell extruded enclosures with previous projects and love the build quality and the fact that they incorporate a slot in the sides which let me insert a sheet of PCB material on which I can do the assembly.<\/p>\n

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

Referring to the schematic drawing in Peter\u2019s video, you can see that the variable capacitor \u201cfloats\u201d above ground, which is not the usual application for these devices. To do that I mounted the vari-cap on a piece of non-plated PCB material that I cut to the width of the enclosure and it fit nicely within the slot. The vari-cap had three pins on the side of the frame that allowed me to force fit it into three holes I drilled in the PCB material. I was very careful to drill the holes undersize and then slowly open them up until the vari-cap press fit on to the board. For good measure I ran UV curing adhesive down into each hole, letting it flow all the way through before I set it with a UV light source.<\/p>\n

\"\"<\/a>I then drilled an oversized hole in the front panel for the vari-cap shaft to pass through.<\/p>\n

\"\"<\/a>I then mounted the RF gain and band switch. The next step was the assembly of the AM broadcast filter. As SDRs can be overpowered by local AM radio stations Peter choose to include an internal band pass filter that is configured for around 3.5 MHz. The intent of this filter is to attenuate the signals below 3.5 MHz. Strong AM stations will still be heard but there is much less chance of them bleeding through on the higher frequencies.<\/p>\n

\"\"<\/a>I assembled the filter on a piece of perf board and connected the component leads on the bottom. I passed leads back up through the perf board for the signal path and ground. I mounted it on the main board with a standoff.<\/p>\n

\"\"<\/a>The next step was the wiring of the inductors to the rotary switch. Simple, and I tied them to the vari-cap frame.<\/p>\n

\"\"<\/a>For the back panel I chose an SO-239 and a BNC for the antenna input, and for the radio connection an SMA and another BNC. I sanded off the coating on the enclosure at the antenna mounts as well as the four corners where the back panel screws into the top and bottom of the clam shell enclosure to provide good grounding of the enclosure. I wired the 1N4148 diodes on the antenna connectors, and attached the RG-174 coax. As Peter suggested, I grounded the long (relatively speaking) runs to and from the back panel with coax and grounded it at the back panel.<\/p>\n

\"\"<\/a>The last step was to apply a bit of epoxy adhesive to the fiberglass board and the slot it runs in to hold it in place. Once the epoxy set, I did the final wiring of the front and rear panel components. You can see how I sanded the corners of the back panel in the above photo.<\/p>\n

\"\"<\/a>I connected it to my inverted L antenna and an SDR Play RSP2 and gave it a test run. I like the fact that I can visually see the changes to the signal strength on the SDR software as well as audibly. It makes a noticeable improvement to the reception.<\/p>\n

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

Thank you Peter. I enjoyed the build.<\/p>\n

Steve Allen, KZ4TN<\/p>\n","protected":false},"excerpt":{"rendered":"

Many thanks to SWLing Post contributor Steve Allen (KZ4TN), who shares the following guest post: SDR Signal Enhancer by Steve Allen I came across this HF Signal Enhancer for SDR on the RTL-SDR.com website. It was designed and built by Peter Parker, VK3YE from Melbourne, Australia. Below is the link to the video of the […]<\/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":[8,3194,627,433,3,43,158],"tags":[4358,6460,157,4087,8865],"class_list":["post-61594","post","type-post","status-publish","format-standard","hentry","category-articles","category-guest-posts","category-how-to","category-mediumwave","category-news","category-shortwave-radio","category-software-defined-radio","tag-homebrew","tag-peter-vk3ye","tag-sdr","tag-software-defined-radio","tag-steve-allen-kz4tn"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pn3uc-g1s","jetpack-related-posts":[{"id":20767,"url":"https:\/\/swling.com\/blog\/2016\/08\/ivans-preliminary-review-of-the-new-rtl-sdr-dongle-on-shortwavemediumwave\/","url_meta":{"origin":61594,"position":0},"title":"Ivan’s preliminary review of the new RTL-SDR dongle on shortwave\/mediumwave","author":"Thomas","date":"August 22, 2016","format":false,"excerpt":"Many thanks to SWLing Post contributor, Ivan Cholakov (NO2CW), who shares the following video review of the\u00a0new\u00a0RTL-SDR dongle on the\u00a0shortwave\u00a0and mediumwave bands. Ivan notes: This is daytime reception comparison. Nighttime could be a different picture. [The RTL-SDR dongle] tunes and frequency is 100% on spot. Using SDR Sharp you have\u2026","rel":"","context":"In "New Products"","block_context":{"text":"New Products","link":"https:\/\/swling.com\/blog\/category\/new-products\/"},"img":{"alt_text":"RTL-SDR-RTL2832U-e1471375714199","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1-300x243.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":18134,"url":"https:\/\/swling.com\/blog\/2016\/04\/a-38-99-rtl-sdr-with-100-khz-1-7-ghz-coverage\/","url_meta":{"origin":61594,"position":1},"title":"A $38.99 RTL-SDR with 100 Khz – 1.7 GHz coverage","author":"Thomas","date":"April 7, 2016","format":false,"excerpt":"Many thanks to SWLing Post contributor, Bill, who recently shared a link to this very affordable RTL-SDR with wideband coverage. I am not at all familiar with this model, but I do like the enclosure and the fact it has both an HF and UV antenna jack. This must be\u2026","rel":"","context":"In "New Products"","block_context":{"text":"New Products","link":"https:\/\/swling.com\/blog\/category\/new-products\/"},"img":{"alt_text":"RTL-SDR","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/04\/RTL-SDR-e1460028209998.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/04\/RTL-SDR-e1460028209998.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/04\/RTL-SDR-e1460028209998.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":20919,"url":"https:\/\/swling.com\/blog\/2016\/08\/the-rtl-sdr-v-3-dongle-on-shortwave-gary-details-setup-and-reviews\/","url_meta":{"origin":61594,"position":2},"title":"The RTL-SDR V.3 dongle on shortwave: Gary details setup and reviews","author":"Thomas","date":"August 30, 2016","format":false,"excerpt":"Many thanks to SWLing Post contributor,\u00a0Gary Wise (W4EEY), for the following review of the RTL-SDR dongle: Based on your blog post on the Version 3 release of the RTL-SDR dongle I had to buy one. I ordered mine from Amazon for $25, and it came in two days. I have\u2026","rel":"","context":"In "Guest Posts"","block_context":{"text":"Guest Posts","link":"https:\/\/swling.com\/blog\/category\/guest-posts\/"},"img":{"alt_text":"RTL-SDR-RTL2832U-e1471375714199","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1.jpg?resize=525%2C300 1.5x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1.jpg?resize=700%2C400 2x"},"classes":[]},{"id":46267,"url":"https:\/\/swling.com\/blog\/2020\/11\/steve-builds-a-simple-swl-antenna-tuner-that-pairs-brilliantly-with-the-belka-dx\/","url_meta":{"origin":61594,"position":3},"title":"Steve builds a simple SWL antenna tuner that pairs brilliantly with the Belka-DX","author":"Thomas","date":"November 1, 2020","format":false,"excerpt":"Many thanks to SWLing Post contributor, Steve Allen (KZ4TN), who shares the following guest post: A Simple Antenna Tuner for SWL Radios by Steve Allen, KZ4TN After reading 13DKA\u2019s excellent review of the Belka-DSP on SWLing.com a few weeks ago I knew I had to have one! The size, features,\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\/2020\/10\/KZ4TN-Simple-Antenna-Tuner.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":20657,"url":"https:\/\/swling.com\/blog\/2016\/08\/new-rtl-sdr-dongles-feature-hf-reception\/","url_meta":{"origin":61594,"position":4},"title":"New RTL-SDR dongles feature HF reception","author":"Thomas","date":"August 16, 2016","format":false,"excerpt":"Many thanks to SWLing Post contributor, Aaron Kuhn, who writes: [T]he newest v3 http:\/\/RTL-SDR.com\u00a0 RTL2832U USB receivers now have HF reception via Direct sampling over the SMA antenna connector directly out of the box with no hardware modding required. I think this might make it the cheapest, out-of-the-box HF SDR\u2026","rel":"","context":"In "New Products"","block_context":{"text":"New Products","link":"https:\/\/swling.com\/blog\/category\/new-products\/"},"img":{"alt_text":"RTL-SDR-RTL2832U-e1471375714199","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2016\/08\/RTL-SDR-RTL2832U-e1471375714199-1.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":6861,"url":"https:\/\/swling.com\/blog\/2013\/07\/using-the-rtl2832u-20-sdr-for-hf-trunk-tracker-scanning\/","url_meta":{"origin":61594,"position":5},"title":"Using the RTL2832U $20 SDR for HF & trunk-tracker scanning?","author":"Thomas","date":"July 8, 2013","format":false,"excerpt":"In response to our post on inexpensive SDRs based on the\u00a0RTL2832U, Jeff Benedict writes: Here's a website that has a lot of info on cheap SDR gear. \u00a0They have a write-up on an external board which adds HF capabilities. \u00a0I have one but haven't done anything with it yet. http:\/\/www.hamradioscience.com\u2026","rel":"","context":"In "How To"","block_context":{"text":"How To","link":"https:\/\/swling.com\/blog\/category\/how-to\/"},"img":{"alt_text":"DE_DVB_T_1","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2013\/07\/DE_DVB_T_1-300x228.jpg?resize=350%2C200","width":350,"height":200},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/posts\/61594","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/users\/15"}],"replies":[{"embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/comments?post=61594"}],"version-history":[{"count":3,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/posts\/61594\/revisions"}],"predecessor-version":[{"id":61705,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/posts\/61594\/revisions\/61705"}],"wp:attachment":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/media?parent=61594"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/categories?post=61594"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/tags?post=61594"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}