#VSWR
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nerfd.net
ICOM AT-160 AUTOMATIC ANTENNA TUNER (3:1 OFFSET) FOR IC-725, IC-726, IC-728, and IC-729.

Price: Not specified This ICOM AT-160 is designed for use with IC-725, IC-726, IC-728, and IC-729.  It will also work with the IC-706, with a custom cable.  This is a low impedance ATU for matching 50 ohm…
ICOM AT-160 AUTOMATIC ANTENNA TUNER (3:1 OFFSET) FOR IC-725, IC-726, IC-728, and IC-729.
Price: Not specified This ICOM AT-160 is designed for use with IC-725, IC-726, IC-728, and IC-729.  It will also work with the IC-706, with a custom cable.  This is a low impedance ATU for matching 50 ohm loads with a maximum VSWR of 3:1.  7 pin Interface cable is NOT included but available on Ebay for a few View listing Go to Source
www.nerfd.net
November 5, 2026 at 9:00 PM
skunkw0rxx.space
Come to find out the cheap antennas are not so good for use as they came back with a reading of about 2.5. That is, until I bumped it with my hand, then it pegged out over 3.0.
Picture of a VNA screen with a displayed VSWR test reading 2.516 at 915MHz
October 24, 2026 at 8:47 PM
skunkw0rxx.space
One of my friends suggested a better antenna for $12 each. It's test came back with a reading of 1.23, way better than the cheap antenna I bought.

Both are 10dBi antennas, but clearly one is better than the other.
Picture of a VNA screen with a displayed VSWR test reading 1.23 at 915MHz
October 24, 2026 at 8:47 PM
broadwave.bsky.social
Mounted to a customer provided heat sink, conduction cooled fixed attenuators are space saving and lightweight. Contact BroadWave Technologies for a solution to your unique requirement.
#IEEE #RF

broadwavetechnologies.com/conduction-c...
Conduction Cooled Fixed Attenuator Rated 125-Watts Peak Power - Broadwave Technologies
BroadWave Technologies has developed a small, lightweight 50-Watt fixed attenuator. Model 351-374-020 is a space saving 50 Ω, DC-6 GHz, 20 dB attenuator with SMA female connectors. Designed for a commercial aviation application, this conduction cooled fixed attenuator mounts to a customer provided heat sink. The device exhibits 1.15:1 maximum VSWR and a peak power […]
broadwavetechnologies.com
October 22, 2026 at 6:10 PM
bharat-ranganathan.bsky.social
www.youtube.com/watch?v=VSWr...
Weezer "Only in dreams" (Milan, Factory 18FEB1995)
YouTube video by Tape Trading
www.youtube.com
October 19, 2026 at 11:20 PM
skunkw0rxx.space
The stuff on Amazon isn't really reliable and a 10dBi antenna is more like a 6dBi after VSWR testing.
October 16, 2026 at 7:42 PM
n1tx.bsky.social
The installation of the vertical was rushed in the snow. The base is about 4 ft above ground. Manual says 20-30 ft best. Nevertheless, I swept the Comet today with RigExpert. VSWR < 2:1 on 80m, < 1.8:1 on 60m and 40m, and < 1.5:1 on 30-6m. I think I’ll repurpose it for low power backup and SWL.
October 12, 2026 at 8:38 PM
atax1a.infosec.exchange.ap.brid.gy
smokin on that high-impedance shit that gives you a VSWR of 10:1
September 5, 2026 at 7:20 PM
stolztelecom.bsky.social
30 deterministic RF calculators in one workspace.

Link budgets. Coax loss. ERP. VSWR. Fresnel zones. Microwave paths. Intermod. Terrain-shaped coverage. Checked, repeatable, showable.

The AI explains the problem. The calculator does the math.

sentinelrf.ai/features/ #SentinelRF #RFEngineering #LM
August 24, 2026 at 2:31 PM
go-radio-go.bsky.social
気がつくと機材が増えまくっていました。TRX固定器5台、ハンディ4台（内1台家庭内行方不明）、チューナー5台、VSWR計3台、モービルアンテナ3本、ハンディホイップ4本、ノイキャン2台、バランunun数個、スタンドマイク4台、マイク切替器2台、他マイク3個？　書ききれなくなってきた。
#アマチュア無線
August 5, 2024 at 2:20 PM
gerardbinnendijk.bsky.social
Don’t Be a Sucker (1943): A Wartime Film’s Powerful Message Against Prejudice

www.youtube.com/watch?v=vswr...
Don’t Be a Sucker (1943): A Wartime Film’s Powerful Message Against Prejudice
YouTube video by King Rose Archives
www.youtube.com
November 1, 2025 at 12:45 PM
dxhamradiosupply.bsky.social
RFS N Female Connector for 7/8" Coaxial Cable, OMNI FIT™ Premium, Straight, O-Ring and compressed sealing
RFS N Female Connector for 7/8″ Coaxial Cable | DX Ham Radio Supply
RFS N Female connector for 7/8″ coaxial cable. Durable, weatherproof RF connector with low VSWR for LCF78-50 and similar hardline cables.
www.dxhamradiosupply.com
March 10, 2026 at 6:04 AM
m1geo.com
This came out looking OK, and worked a treat, too! Just a simple frame to hold antennas on the car, and with all the seals fitted, there's no whistles from the roof-bars and the VSWR was spot on! Nice!

Just needs a tiny modification to route the coax inside the crossbar. Nice.
Excuse my thumb in the left of the picture, and the slightly out of focus image!
March 23, 2025 at 8:27 PM
nishikazu0417.bsky.social
先日Elecrowに製造を依頼したSatNOGS向けバンドパスフィルタ試作基板(π-pad for test v1)が届いたので,
早速, はんだブリッジでパッドを短絡させTHRUを製作しグランド付きコプレーナ線路の特性をLiteVNAで測定しました！
435MHzでの特性インピーダンスは約43Ω, VSWRは約1.2, 挿入損失はほぼ0dB(校正THRU基準)と伝送線路として良好な特性を得られました. 良かったです.
November 12, 2025 at 12:39 PM
nishikazu0417.bsky.social
フィーダ用の3.5回巻1.5λピッチのヘリカルアンテナと,ダイソーのステンレスボウル(直径24cm)を組み合わせてヘリコーンアンテナ(Helicone, ヘリカルコーンアンテナ)を製作してみました！📡🛰
シミュレーション(OpenMOM)上での想定利得は約12dBiと以前製作した10回巻2.5λピッチのヘリカルアンテナに匹敵しておりサイドローブも抑えられていることから,より良好なSN比を得られることが期待されます.
LiteVNAによる測定では,インピーダンスマッチング後の使用周波数付近でのVSWRは約1.8とやや高いもののスミスチャート上の軌跡からは複共振特性が得られていることがわかります.
January 31, 2024 at 12:35 PM
nishikazu0417.bsky.social
傘をベースにした衛星受信用の直径1m級ストレスドパラボラアンテナ(Stressed dish antenna)のRHCPフィーダとしてLバンドのHRPT受信用, Sバンド受信用にそれぞれ1個ずつ3.5回巻,1.5λピッチのLHCPヘリカルアンテナを製作してみました！📡🛰
それぞれ,OpenMOMによるシミュレーション上での利得は10dBi弱,半値角は約60°となっています.
また,LiteVNA64による測定ではインピーダンスマッチング後の使用周波数周辺でのVSWRはLバンド用が約1.8, Sバンド用が約1.4と比較的良好な特性が得られています.
January 30, 2024 at 8:39 AM
nishikazu0417.bsky.social
430MHz帯(435MHz~438MHz)のアマチュア無線衛星からの電波を受信するためのQFHアンテナを製作いたしました！📡🛰
より広範囲をカバーするために縦横比は0.3としています.
前回の結果を踏まえ設計に変更を行ったところ,LiteVNAを用いた測定にて430MHz帯のほぼ全域でVSWRが1.5以下という良い特性を得ることが出来ました.複共振特性も現れています.
January 19, 2024 at 8:56 AM
nishikazu0417.bsky.social
今後の435MHzのアマチュア無線周波数帯を使用する衛星やJAXAの小型月着陸実証機"SLIM"のLEV-1ローバーからのダウンリンク受信の為に,JAMSATの500円八木アンテナとして知られるWA5VJB氏の"Cheap Yagi Antennas for VHF/UHF"の8エレメント版を製作してみました！📶🛰
材料に合わせ細部にアレンジを加えています.
LiteVNAを用い測定したところ,インピーダンスマッチング後の設計周波数435MHz付近でのVSWRは約1.2となっており, 帯域幅(VSWR<1.5)も15MHz程ありそれなりに良い結果が得られています.
December 25, 2023 at 3:58 AM
nishikazu0417.bsky.social
先日破損してしまったHRPT受信用のRHCPヘリカルアンテナを新たに作り直しました！📡🛰
設計周波数1688MHz,巻数10,ピッチ間隔0.25λです.
前回の設計の反省点などを踏まえ,細部の設計に変更を加えています.
インピーダンスマッチング後の設計周波数付近でのVSWRは約1.8で,今後更に調整を加える予定です.
December 17, 2023 at 2:15 AM
nishikazu0417.bsky.social
先日製作した気象衛星からのHRPT受信用のヘリカルアンテナについてですが,インピーダンスマッチングを取るためにアルミテープと薄い銅板を用いて容量成分を簡易的に追加したところ,対象周波数でのVSWRを1.5以下に抑える事が出来ました！📡🛰
明日,実際に受信を試みて,利得への影響を確かめてみたいと思います.
December 7, 2023 at 11:06 AM
wildylion.bsky.social
Careful with disconnecting the antennas! You should never operate any transmitter with antenna disconnected, or else all the generated RF power reflects back in and burns the final stage.

Hopefully this thing has good VSWR protection (being a rugged device, probably it does).
August 15, 2026 at 5:37 AM
n8dmt.mastodon.radio.ap.brid.gy
Completed a few tests on the 2.4 GHz RF Equipment (RFE) components for the single-band Pluto transceivers. TLDR: All looks good and ready to continue evaluating controller software. Details at the qsl.net blog. #hamradio #sdr
https://qsl.net/n8dmt/24-ghz-pluto-rf-equipment/index.html
VSWR for the TECOM 2.4 GHz antennas showing under 1.5:1 over the 2.39 to 2.45 GHz band. Photo of the UTE Microwave RF circulator being tested for forward insertion loss and frequency coverage. This unit covers 2-4 GHz and provides more than 20 dB of reverse isolation. SATSAGEN measurement for the UTE Microwave circulator showing forward passband of 2 to 4 GHz. SATSAGEN measurement of UTE Microwave circulator showing greater than 20 dB of isolation in the reverse path.
November 26, 2025 at 9:21 PM
n8dmt.mastodon.radio.ap.brid.gy
Ever wonder what the input impedance/VSWR is for your inexpensive TinySA-Ultra spectrum analyzer? The specs page provides this info: Input impedance 50 ohm when input attenuation set to 10dB or more. Decided to measure one with a CMT R54 vector analyzer to see […]

[Original post on mastodon.radio]
Screen capture for S11 of the tinySA-Ultra input impedance between 85-5400 MHz. Input attenuator is set to 0 dB. Screen capture the tinySA-Ultra input VSWR between 85-5400 MHz. Input attenuator is set to 0 dB. Screen capture for S11 of the tinySA-Ultra input impedance between 85-5400 MHz. Input attenuator is set to 10 dB improving the match into the system. Screen capture the tinySA-Ultra input VSWR between 85-5400 MHz. Input attenuator is set to 10 dB improving the match and reducing the VSWR.
July 15, 2025 at 8:01 PM
n8dmt.mastodon.radio.ap.brid.gy
Used a magic white sponge with some H2O to clean out the residual sticky-foam from inside my Agilent 85033C calibration kit wooden case. Was a real mess when I started… After drying and brushing out, not so bad (clean enough to use to store calibration kit […]

[Original post on mastodon.radio]
Photo showing a wooden box containing multiple RF calibration kit items: open, short, load, center pin gauge, VSWR standards, between series adapters, and more.
July 15, 2025 at 7:28 PM
n8dmt.mastodon.radio.ap.brid.gy
What to do when you don’t have any of the GR 874-LK20 fancy adjustable length coaxial lines? TLDR: Just keep adding in sets of coaxial adapters until you hit the phase angle (delay) you’re looking for. In this case, understanding for both VHF and UHF bands […]

[Original post on mastodon.radio]
Photo of a vector impedance probe and a bunch of N-connectors and cables on a desktop. Both male to male and female to female, as well as right angle adapters are shown. A variety of VSWR loads are at the top of the photo. Screen shot for the 10:1 VSWR test load directly connected to the vector impedance probe. Load impedance can be changed to rotate clockwise around the chart by adding in various lengths of adapters/cables. This is useful for testing transmitters into various complex load impedances.
July 13, 2025 at 4:09 PM