/Built/L23HP.doc
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12/27/2017
25 watt output power level with additional options such as a mast mount preamplifier control and a
remote DC power control.
What is the same as the past is the RF and IF configurations and drive level options. The
transverter may be configured with common or split IF at any drive level between -20dBm to 10
Watts. This can be changed easily at any time by the user. All IF connections are made through
standard BNC connectors. The RF configurations are separate TX and RX ports or a common RF.
An onboard relay is standard and may be reconfigured at any time. The RF ports are type N
connectors only. Keying the transverter is done by either a voltage (PTT-H) or a ground on
transmit (PTT-L) through the AUX connector which also contains the Sequencer outputs and
additional any requested additional options. The DC cabling and AUX connections are supplied.
Configuration Overview:
The DEM L23HP transverter is designed to interface to all modern
amateur radio transceivers but has been specifically configured to your transceiver’s specifications.
As indicated on the front page, some user options and configurations need to be selected before
delivery but may be user changeable. Let’s review your configuration and verify that your interface
will be easy and trouble free. Please refer to the front page chart for the following.
DEMI Part Number Verification:
IMPORTANT:
The transverters operating bandwidth is restricted by first your IF frequency
bandwidth and secondly, by the Band Pass filters utilized in the design. The usable RF bandwidth
is approximately 1280-1300 MHz
All DEMI transverters contain the operating band within the part
number, i.e., L23HP equates to the 23 centimeter band. (1260-1300 MHz) Since this is the first
transverter design that has a user selectable IF frequency, we simply indicate what the transverter
is “Set For” under the Serial Number on the front page. The configured IF frequency is what we
have on record as your request. If this is incorrect or your desires have changed, it is not a problem
and will be discussed in a section of this manual entitled “If Frequency Selection”.
RF Output :
Next is the maximum linear output power level of the transverter that should not be
exceeded if linear operation is expected. The
“Other Notes”
section will indicate if a custom
output level was selected. In most cases, the transverter is capable of higher output power but is
not recommended because of excessive “on the air” distortion products.
Noise Figure and Gain:
The noise figure and gain listed are the minimum requirements. All
transverters meet or exceed these specifications. Utilizing the latest PHEMPT and SAW filter
technology, we have designed a receiver chain for gain management, IMD performance, and noise
figure to eliminate over load and out of band interference maintaining a stable, quiet, sensitive
receiver. Please note. The noise figure of the transverter is always better through a separate RX
connector and not through the Common Antenna connection.
DC Power Requirement:
Always choose the correct level of fusing for protection.
The DC power requirement is listed and should be used as a guideline.
Please include some “Buffer” in your power supply to eliminate voltage drop delivered to the
Transverter. If a custom lower power is requested, a lower current power supply may be utilized.
IF Option:
The IF option has two choices. A
“Common”
IF connector in which both TX and RX
IF frequencies are conducted through a single connector, or “
Split”
IF connections with a separate
connector for the receive and transmit connections to your transceiver.
