RX Share Audio Switch DXE-RXSHARE DXE-RXSHARE-INS Revision 0 DX Engineering 2018 1200 Southeast Ave. - Tallmadge, OH 44278 USA Phone: (800) 777-0703 Tech Support and International: (330) 572-3200 Fax: (330) 572-3279 E-mail: DXEngineering@DXEngineering.com
Introduction Multi-operator contesting is challenging, especially when a pair of operators are unable to hear what the other operator is hearing. DX Engineering presents an elegant but simple solution with the RX SHARE Audio Switch a flexible switching device that allows two operators to hear exactly what they want to hear, whenever they want to hear it. Audio from two separate radios or one shared radio can be controlled by either operator s three-position rocker switch to select the specific audio they want fed to their stereo headphones. With the RX SHARE placed between each operator, these selections can be changed independently by each operator quickly and easily, at will and on the fly, with the light-touch rocker switches. The RX SHARE has been extensively tested and used in competition by experienced, world-class contesters. Multi-operator contesting in the Multi-Two or Multi-Single category often involves simultaneous use of separate radios on a single band or on two different bands. The run operator calls CQ and makes a constant string of contacts on one frequency. Meanwhile, the second operator searches for new stations. Limited to transmitting only one signal at a time, the ops take turns as soon as a new contact becomes available. Using the RX SHARE in the SEPARATE RADIOS mode, each operator may choose to listen to the Radio 1 audio or the Radio 2 audio in both ears. Or, at any time either operator can listen to the audio from one radio in each ear, allowing better coordination and fewer interruptions. This translates to a higher QSO rate, higher scores and less operator fatigue! A single-operator using two radios in SO2R Single-Op, 2 Radios mode has similar needs. The operator may want to focus on just one of the radios, listening to the same audio in both ears. Or the operator can hear the audio from each radio in one ear, allowing simultaneous CQ-ing and tuning for new contacts. Advanced operators can even manage two pileups at once on different bands! Doing these things effectively requires the easy, intuitive audio control provided by the RX SHARE. When one radio is shared by two operators, common during Field Day or training activities, the RX SHARE is placed in the SHARED RADIO mode. Both operators can share the receive audio or audio from a sub-receiver, if available, can be selected by either operator. The RX SHARE provides a convenient way of splitting the audio output of a single radio. - 2 -
In a contest situation, using a transceiver equipped to split the audio feed from the MAIN and SUB receivers to the left and right headphone channels, each operator can choose to listen to either the MAIN receiver or the SUB receiver in both ears, or to hear the MAIN in one ear and the SUB in the other ear. One operator will be able to hear when a new station is ready to be worked, or when the other operator is going to work them. Using the DXE-RXSHARE provides complete control of the radio audio feed to two separate stereo headphones. Audio from typical radio headphone jacks to the DXE-RXSHARE input phone jacks are quickly and easily connected with user supplied patch cables with 1/4 inch (6.35 mm) stereo phone plugs at each end. The unit features two sets of stereo headphone outputs including 1/4 inch (6.35 mm) and 1/8 inch (3.5mm) stereo jacks to accommodate headphones or headsets with either type of plug - you ll never hunt for an adaptor again! Audio levels are controlled by the transceiver AF Gain controls. The DXE-RXSHARE is built into a heavy steel and stainless steel chassis with four large rubber feet, so it will not slide around the desk when the switches are operated. The switch panel is clearly marked for every configuration and operating scenario. RX SHARE Audio Switch Features and Specifications: Quick connections from radios to RX SHARE via 1/4 in. stereo audio input (patch cables required depend on transceiver headphone jacks and cable length desired) Four stereo headphone output connections available two of each size for each operator- 1/4 inch (6.35 mm) and 1/8 inch (3.5 mm) extra headphone outputs may be used for recording purposes Center rocker switch to quickly choose the RX SHARE mode, SEPARATE RADIOS or SHARED RADIO Two separate and silent rocker switches at ideal height to make independent operator audio selections Both operators may select audio from Radio 1, Radio 2 or both in SEPARATE RADIOS mode Both operators can select audio from MAIN or SUB or both in SHARED RADIO mode that supplies MAIN and SUB receiver audio separately to headphone L and R Unit stays in place on desk during use - Large, heavy stainless and powder coated steel chassis weighs 3.75 lbs. and measures 10.50 x 2.50 x 3.25 in. (WHD) Stud and wing nut (#10) on rear stainless steel panel for station grounding All connections on rear panel for proper cable management and a clear operating desk Passive audio device requires no DC power Internal jumpers allow audio impedance selection for different radio and headphone combinations DX Engineering brings innovation and convenience to contest stations, club operations and multiradio ham shacks. The DXE-RXSHARE Audio Switch is ready to supply just the right audio for your operations. - 3 -
Additional Parts Required, Not Supplied with the DXE-RXSHARE Stereo capable headphones 1/4 inch (6.35 mm) or 1/8 inch (3.5 mm) stereo audio jumper cables to connect the RX SHARE to the radio stereo headphone jack. Station ground connection cable Manual Updates Every effort is made to supply the latest manual revision with each product. Occasionally a manual will be updated between the time your DX Engineering product is shipped and when you receive it. Please check the DX Engineering web site (www.dxengineering.com) for the latest revision manual. Installation Installation is straight forward. The rear panel on the RX Share is shown below with an example showing connection from the RX SHARE to the headphone jacks on two Icom-7610 radios and connection to two Heil headsets. Additionally, there is a connection for the station ground to help avoid any ground loops in the audio lines. - 4 -
Internal Jumpers There are 9 jumpers inside the RX SHARE Jumpers H1 through H9. Access to the inside is done by removing the four Phillips head screws that hold the case together. Audio Impedance Jumpers H2-H9 The audio impedance jumpers select different winding configurations of the audio isolation transformers to vary input and output impedance. Most radios and headphones will not require changing jumpers H2-H9 from their default 150 ohm position. If the headphone audio is loud enough and does not require turning the receiver AF GAIN controls to an extreme position, you do not need to move the jumpers. Jumpers H2 & H3 are for Operator 1 output audio from the RXSHARE. Jumpers H4 & H5 are for Radio 1 input audio to the RXSHARE. Jumpers H8 & H9 are for Operator 2 output audio from the RXSHARE. Jumpers H6 & H7 are for Radio 2 input audio to the RXSHARE. -5- - 5 -
The jumpers must be moved as a pair - both in the 150 ohm or both in the 600 ohm positions or there will be no audio output. If you have high-impedance headphones with low audio levels, move the output audio jumpers from 150 ohm to 600 ohm. If your receiver audio output is low at normal control settings, move the input audio jumpers from 150 ohm to 600 ohm. If the operators are using headphones with greatly different impedances or the operators have large differences in hearing sensitivity, experiment with different settings of the jumpers to find the best balance. It may be easiest to simply have both operators use the same type of headphones. Ground Jumper H1 The ground jumper is provided to allow control of input and output audio grounding. The default is for the jumper to be in the INPUT position so the input audio common circuit is connected to the enclosure. (The enclosure also has a ground terminal on the back panel for connection to the station ground system.) All stations have different configurations of wiring and RF field strengths vary greatly so in some cases, moving the jumper from the INPUT to the OUTPUT, connecting the headphone common circuit to the enclosure or removing the jumper entirely may avoid RFI to the audio. The audio isolation transformers break the direct path for RF between the input and output circuit. No combination of ground jumper setting will damage the RXSHARE or any connected equipment in any way - feel free to experiment if you experience RFI in the audio. Troubleshooting Audio Problems A sinusoidal 60 Hz (or 50 Hz outside the US and Canada) tone (i.e. "hum") is most likely caused by a magnetic field from a power transformer or ac wiring. Move audio cables away from the source of the field and minimize cable lengths to reduce hum. A sharper "buzz" at 120 Hz (or 100 Hz) is caused by rectified ac power or currents flowing on the ac neutral of your power wiring. Bonding equipment to a station ground bus or directly from enclosure to enclosure is most likely to reduce buzz. Cross-talk between the audio outputs of each radio may be due to the audio common conductor of the radio-to-rxshare cable being broken or too light. Use good-quality shielded cables to avoid cross-talk. Bonding of the radios to a common ground bus or directly together also reduces crosstalk. If RF is being picked up in the headphones, first check that the headphone common conductor is not broken or compromised. Moving the RXSHARE internal ground jumper from INPUT to OUTPUT may help. Keep cable lengths to a minimum, as well. - 6 -
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Technical Support If you have questions about this product, or if you experience difficulties during the installation, contact DX Engineering at (330) 572-3200. You can also e-mail us at: DXEngineering@DXEngineering.com For best service, please take a few minutes to review this manual before you call. Warranty All products manufactured by DX Engineering are warranted to be free from defects in material and workmanship for a period of one (1) year from date of shipment. DX Engineering s sole obligation under these warranties shall be to issue credit, repair or replace any item or part thereof which is proved to be other than as warranted; no allowance shall be made for any labor charges of Buyer for replacement of parts, adjustment or repairs, or any other work, unless such charges are authorized in advance by DX Engineering. If DX Engineering s products are claimed to be defective in material or workmanship, DX Engineering shall, upon prompt notice thereof, issue shipping instructions for return to DX Engineering (transportation-charges prepaid by Buyer). Every such claim for breach of these warranties shall be deemed to be waived by Buyer unless made in writing. The above warranties shall not extend to any products or parts thereof which have been subjected to any misuse or neglect, damaged by accident, rendered defective by reason of improper installation, damaged from severe weather including floods, or abnormal environmental conditions such as prolonged exposure to corrosives or power surges, or by the performance of repairs or alterations outside of our plant, and shall not apply to any goods or parts thereof furnished by Buyer or acquired from others at Buyer s specifications. In addition, DX Engineering s warranties do not extend to other equipment and parts manufactured by others except to the extent of the original manufacturer s warranty to DX Engineering. The obligations under the foregoing warranties are limited to the precise terms thereof. These warranties provide exclusive remedies, expressly in lieu of all other remedies including claims for special or consequential damages. SELLER NEITHER MAKES NOR ASSUMES ANY OTHER WARRANTY WHATSOEVER, WHETHER EXPRESS, STATUTORY, OR IMPLIED, INCLUDING WARRANTIES OF MERCHANTABILITY AND FITNESS, AND NO PERSON IS AUTHORIZED TO ASSUME FOR DX ENGINEERING ANY OBLIGATION OR LIABILITY NOT STRICTLY IN ACCORDANCE WITH THE FOREGOING. DX Engineering 2018 DX Engineering, DXE, DX Engineering, Inc., Hot Rodz, Maxi-Core, DX Engineering THUNDERBOLT, DX Engineering Yagi Mechanical, EZ-BUILD, TELREX, Gorilla Grip Stainless Steel Boom Clamps, Butternut, SkyHawk, SkyLark, SecureMount, OMNI-TILT, RF-PRO-1B, AFHD-4 are trademarks of PDS Electronics, Inc. No license to use or reproduce any of these trademarks or other trademarks is given or implied. All other brands and product names are the trademarks of their respective owners. Specifications subject to change without notice. - 8 -