{"product_id":"rdl-acm-3","title":"RDL ACM-3 – FM Transmitter Amplitude Component Monitor","description":"\u003ch2\u003eWhat is the RDL ACM-3?\u003c\/h2\u003e\u003cp\u003eThe RDL ACM-3 is an amplitude component monitor for FM broadcast transmitters that measures synchronous AM noise, the bandwidth variations that aggravate multipath artifacts in listeners' receivers. RDL describes its ACM technology as the time-proven, industry-accepted method of controlling synchronous AM noise, used by FM stations in every major U.S. market. It gives engineers the accurate AM measurement and continuous monitoring needed to tune any transmitter, new or old, for optimum bandwidth performance.\u003c\/p\u003e\u003ch2\u003eHow does it work?\u003c\/h2\u003e\u003cp\u003e\u003cimg src=\"https:\/\/rdlnet.com\/wp-content\/uploads\/2024\/01\/acm-3.jpg\" alt=\"RDL ACM-3 FM amplitude component monitor\" style=\"max-width:100%;height:auto\" loading=\"lazy\"\u003e\u003c\/p\u003e\u003cp\u003eThe ACM-3 takes the filtered transmitter carrier on a BNC input, accepting up to 30 V combined filtered carrier plus AM. Its front-panel display measures synchronous AM from -20 dB to -69 dB, and a BNC oscilloscope jack extends the range from -10 dB to -90 dB at 5 V p-p full scale. Residual noise is more than 95 dB below 100% amplitude modulation, and THD of the recovered AM is below 0.03%. A +4 dBu audio output at 100 Ω source impedance carries the recovered AM, and a DC output provides a level representing significant synchronous AM. With continuous monitoring, stations can maintain clarity, maximize loudness and stereo separation, reduce subcarrier crosstalk and keep signal coverage consistent. The ACM-3 runs from an 18 Vac external supply included for North America and measures 1.7 x 5.8 x 4.1 in. RDL lists Rack-Up mounting options, including the \u003ca href=\"https:\/\/creationnetworks.net\/products\/rdl-ru-br1\"\u003eRDL RU-BR1 bracket\u003c\/a\u003e, \u003ca href=\"https:\/\/creationnetworks.net\/products\/rdl-ru-sma1\"\u003eRU-SMA1 mounting plate\u003c\/a\u003e, \u003ca href=\"https:\/\/creationnetworks.net\/products\/rdl-hr-ru1\"\u003eHR-RU1 adapter kit\u003c\/a\u003e, \u003ca href=\"https:\/\/creationnetworks.net\/products\/rdl-mb-1\"\u003eMB-1 mounting kit\u003c\/a\u003e and \u003ca href=\"https:\/\/creationnetworks.net\/products\/rdl-dra-35r\"\u003eDRA-35R DIN rail adapter\u003c\/a\u003e.\u003c\/p\u003e\u003ch2\u003eWhat are the key features?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSynchronous AM measurement\u003c\/strong\u003e — Measures the FM bandwidth variations that cause multipath artifacts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide measurement range\u003c\/strong\u003e — -20 dB to -69 dB on the front panel and -10 dB to -90 dB on the scope jack.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOscilloscope output\u003c\/strong\u003e — BNC scope jack at 5 V p-p for full-scale display.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAudio and DC outputs\u003c\/strong\u003e — A +4 dBu audio output and a DC level output representing significant synchronous AM.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVery low residual noise\u003c\/strong\u003e — Better than 95 dB below 100% amplitude modulation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTransmitter tuning aid\u003c\/strong\u003e — Supports tuning for loudness, stereo separation and consistent coverage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePower supply included\u003c\/strong\u003e — Ships with an 18 Vac external supply for North America.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRack-Up mounting\u003c\/strong\u003e — Mounts with RDL Rack-Up series accessories.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWhere is it typically used?\u003c\/h2\u003e\u003cul\u003e\u003cli\u003eBroadcast studio\u003c\/li\u003e\u003c\/ul\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003cdiv style=\"overflow-x:auto;-webkit-overflow-scrolling:touch\"\u003e\u003ctable style=\"border-collapse:collapse;width:100%;min-width:300px;table-layout:fixed\"\u003e\n\u003ccolgroup\u003e\n\u003ccol style=\"width:44%\"\u003e\n\u003ccol style=\"width:56%\"\u003e\n\u003c\/colgroup\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eModel\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003eACM-3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eInput\/Output Connector\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003eBNC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eMaximum Input Signal\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e30 V (combined filtered carrier + AM)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eMeasurement Range\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e-20 dB to -69 dB (front-panel display), -10 dB to -90 dB (front-panel scope jack)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eResidual Noise\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e\u0026lt; 95 dB below 100% amplitude modulation\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eOscilloscope Jack\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003eBNC 5 V p-p for full-scale display\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eAudio Output\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e+4 dBu, 100 Ω source impedance\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eTHD of recovered AM\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e\u0026lt; 0.03%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eDC Output\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003eDC level representing significant synchronous AM\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eAmbient Operating Environment\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e32° F to 122° F (0° C to 50° C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003ePower Requirement\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e18 Vac, external supply included (North America)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eDimensions\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e1.7 in. x 5.8 in. x 4.1 in., (4.1 cm x 15.0 cm x 10.4 cm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003c\/div\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eWhat does the ACM-3 measure?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eSynchronous AM noise on an FM transmitter, the bandwidth variations that aggravate multipath artifacts in receivers.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eWhat is its measurement range?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003e-20 dB to -69 dB on the front-panel display and -10 dB to -90 dB through the oscilloscope jack.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eHow does it connect to the transmitter?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eThrough a BNC input accepting up to 30 V combined filtered carrier plus AM.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eIs a power supply included?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eYes. An 18 Vac external supply is included for North America.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eHow is it mounted?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eRDL recommends its Rack-Up series mounting options, such as the RU-BR1, RU-SMA1 and HR-RU1.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eWhat warranty does it carry?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eThis product is covered by a 7-year RDL warranty. For warranty claims, RMAs or support, contact Creation Networks at (888) 230-3661 or sales@creationnetworks.net.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eCan Creation Networks help design the system?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eYes. Our team specifies, programs and installs broadcast monitoring systems for commercial projects nationwide. Call (888) 230-3661 for a quote or design review.\u003c\/p\u003e\u003c\/details\u003e","brand":"RDL","offers":[{"title":"Default Title","offer_id":68025753469164,"sku":"ACM-3","price":1189.66,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0603\/7982\/4364\/files\/acm-3.jpg?v=1793583458","url":"https:\/\/creationnetworks.net\/products\/rdl-acm-3","provider":"Creation Networks","version":"1.0","type":"link"}