DX Engineering DXE-RG5000HD Instruction Manual

Receiver Front-End Protector

DX Engineering - 1200 Southeast Ave. - Tallmadge, OH 44278 USA

Phone: [phone] ∙ Tech Support and International: [phone]

Fax: [phone] ∙ E-mail: [e-mail]

Receiver Guard 5000HD

DXE-RG-5000HD

DXE-RG-5000-INS Rev 2

© DX Engineering 2019

Introduction and General Information

The DX Engineering Receiver Guard 5000HD is an advanced
electronic receiver RF limiter that was developed over years of
extensive research and testing. The rugged DXE-RG-5000HD
offers performance superior to other devices on the market,
covering 0.5 to 150 MHz with under 0.15 dB of insertion loss.
(<0.15 dB at 50 MHz and <0.3 up to 150 MHz). These highly
effective and inexpensive receive RF limiters prevent front-end
damage due to high RF levels that can result in costly radio repairs.

The DX Engineering DXE-RG-5000HD Receiver Guard should
be used on any radio receive only antenna input for low-cost

front-end “insurance” in these common RF situations, among others:

 Receive antennas in very close proximity to transmit antennas
 Field-day operations with many transmitters in close range
 Multi-transmitter contesting sites
 Neighboring Amateur and CB operators
 Frequent high-power mobile encounters

DX Engineering Receiver Guards provide automatic protection for receive equipment applications:

 The DXE-RG-5000HD works for all radios and offers the ultimate performance required by the upper

tier of transceivers tested to have the best narrow-spaced third-order dynamic range or published RMDR
(Reciprocal Mixing Dynamic Range).

It has been confirmed with extensive testing and real world use that these inexpensive Receiver Guards offer the
best available protection for your transceiver or receiver investment. Combined with RF filters, placed on the
antenna side of the Receiver Guard, exceptional signal control and protection is possible. DX Engineering offers
the highest level of protection for your receiver’s front end.

The Receiver Guard was developed specifically to protect the crucial receiver front-ends of expensive high
performance transceivers at contesting super-station, K3LR. At this world class multi-transmitter contest station,
dedicated receive antennas are exposed to high levels of RF radiated from close-by transmit antennas. DXE-RG-
5000HD Receiver Guard’s multi-stage receive input protectors employed at K3LR have never failed, as none of
the expensive radios have ever required front-end repairs. And they keep on racking up great scores at K3LR,
even in the harshest of receiving environments. Why? Because, the DX Engineering Receiver Guard produces far
lower harmonic and noise products across the spectrum than any competing RX front-end saving device, allowing
competitive contest operations to continue unfettered!

At the heart of each Receiver Guard is a highly effective electronic RF limiter covering 500 kHz to 150 MHz with
an insertion loss under 0.15 dB at 50 MHz and under 0.3 dB to 150 MHz. The multi-stage design includes a gas
discharge tube for maximum pulse energy protection. The Receiver Guard is a passive electronic limiter, not a
filter, so competitive contesting stations must still use separate band filters. For example, the Receiver Guard HD
limiter can reject 10 watts of catastrophic receive antenna feedline RF while passing a signal of about 87 dB over
S-9, which is only 25 mw. That level is well under the point of front end damage.

When there are high levels of RF on your receive antennas, DX Engineering’s Receiver Guards generate far less
harmonic noise than other limiters on the market, which allows your station to continue to operate safely and
competitively. At normal HF signal levels Receiver Guard operates continuously with no effect on the

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performance of your station while providing the best possible protection for your radio. The Receiver Guard does

This is a Receive Only Accessory

Do not connect the DXE-RG-5000HD Receiver Guard

to a transmitter output

DO NOT TRANSMIT through the Receiver Guard

The Receiver Guard is is NOT a filter. The Receiver Guard operates by clamping or limiting

very strong RF signals

not pass DC. If you are using the Receiver Guard in a system that requires a DC voltage, insert the DC as shown
in Figure 7.

Features

 Keeps stray high levels of RF from damaging your receiver input
 Ideal for separate 160 and/or 80 meter receive systems
 Uses state of the art components for maximum protection of receivers
 Under 6 nsec response time
 Multi-Stage protection
 Very low insertion loss
 Uses BNC type connectors to avoid accidently connecting to a transmit line
 Has been developed and tested in a world-recognized multi-multi contest station

Specifications - DX Engineering Receiver Guard

Frequency Range: 0.5 through 150 MHz
Insertion Loss: < 0.15 dB at 50 MHz, < 0.3 dB 50 MHz up to 150 MHz
VSWR: < 1.2:1
Max Output Level: RG-5000HD: +14 dBm at 10 W input. RG-5000: +10 dBm at 10 W input.
Maximum Power Handling: 10 W CCS (Continuous Commercial Service)
System Impedance: 50 to 75 ohms, unbalanced
Connectors, Input and Output: BNC

Operations with the DX Engineering Receiver Guard

Receiver front-end circuitry is susceptible to damage from very strong signals arriving via the antenna from
nearby high power transmitters. Dedicated receivers and certain transceivers with separate receive-only antenna
inputs generally lack protection from unintended overload and damage.

Dedicated band pass, low pass and high pass filters offer high levels of protection in engineered systems.
However, they are generally expensive and are designed to handle specific offending signals. Other front-end
saving units temporarily disconnect the receiver input for a high level of protection, but they require extra keying
connections. Plus, rapidly keyed relays that produce noise and pulses cannot be used on receive antennas in
contesting stations.

The Receiver Guard is an advanced multi-stage receive signal limiting device that is virtually RF transparent at
normal receiving levels, all the way up to -10 dBm, or approximately 63 dB over S-9. In typical operations,
installed on the RX Input of the transceiver or dedicated receiver, you cannot tell that the limiter is installed. At

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slightly higher than normal receive antenna input RF levels, the Receiver Guard has a specially designed

This is a Receive Only Accessory - Do not connect the DXE-RG-5000HD Receiver Guard

to a transmitter output

DO NOT TRANSMIT through the Receiver Guard

The Receiver Guard is is NOT a filter. - The Receiver Guard operates by clamping or limiting very

strong RF signals

mechanism of limiting that reflects higher than normal levels of RF energy while generating minimal harmonics
and noise. That, plus it has extremely low insertion loss are the most important differences between the Receiver
Guard and other protection devices.

What happens if the receive antenna is extremely close to the transmit antenna, or there is an antenna support or
other system failure that causes a high RF level to enter the receive antenna input? The DX Engineering
Receiver Guard can save the day!

Some Amateur Radio Operators have an antenna installation arrangement where their Beverage wire antenna, or
other receive antenna, is installed in close proximity to the transmit antenna. With the Receiver Guard installed,
when RF signal levels on the receive antenna line rise above the -10 dBm level, the specially designed circuit
limits the output signal, with a resulting rise in the input SWR. The Receiver Guard 5000HD can dissipate a
continuous 3 watts input, while only allowing only a 76 dB over S-9 signal out to the receiver. Ultimately, the
Receiver Guard 5000HD can handle a continuous 10 watt input, allowing no more than +10 dBm (0.010 watts)
output, which is only 83 dB over S-9 (The Receiver Guard 5000HD is +14 dBm [0.025 watts] output, which is
over 87 dBm over S-9) to the receiver front-end, preventing damage, while the reflected energy at the Receiver
Guard input is nearing 100%. To help prevent catastrophic damage to the receive input from an extremely high
RF level, the Receiver Guard contains a modern gas discharge tube, a fast acting clamp component at the antenna
input connector.

Some good scenarios:

Separate Receiving Antennas (a Beverage receiving antenna, for example): If a receiving antenna is located too

close to the transmitting antenna, RF power can flow back into the receiving line during transmit. The Receiver
Guard will limit stray RF energy presented to the receiver (or other sensitive devices such as a preamp).

Contest Stations: There are many different configurations of contest stations. If it is possible to be receiving on
one radio while another is transmitting, a Receiver Guard would make good sense to use. If the radios are on
different bands, and if there is substantial filtering on each band, then the Receiver Guard might not be necessary.
The Receiver Guard is a good ‘insurance policy’ to have in case one of the filter/band/antenna settings is
incorrect, and high levels of RF energy is accidentally applied to a receiver.

Skimmer Antennas: Many stations run a CW skimmer, where bands are monitored for CW activity and
automatically decoded by the skimmer software running on a PC. The skimmer antennas are usually located in the
same area as all of the normal station antennas. If a transmitter is keyed, the receiving antenna can pick up
substantial RF power, especially if resonant. The Receiver Guard will protect the skimmer receiver. The Receiver
Guard would be installed between the antenna and the SDR antenna input.

High Power AM Station Nearby: The Receiver Guard is not a filter. If the bothersome RF source is a constant
high power broadcast station, the Receiver Guard will reduce the AM energy, but it will also reduce all desired
signals as well. The limiting is not frequency specific. Therefore, if a strong signal on 1 MHz causes 20 dB of

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