To minimize ground loops in sensitive test applications, the input and each of the six outputs is transformer coupled and DC blocked. RF connectors are ground-isolated BNC. A jumper allows the input to be terminated in 50 ohms, or to present a high impedance.
An optional bandpass filter can be installed to reduce spurious responses. Because of the various center frequencies and filter designs that might be desired, TAPR does not offer the filter components. Also, installing the filter may result in reduced phase stability over temperature changes, so we recommend that the filter not be used unless it is really needed.
Typical phase noise performance is -140dBc (1Hz) at >100Hz offset.
The 12 volt power input is fused and protected against reverse polarity. Current drain depends on the number of loads and ranges from 50 to 150ma.
The RF and DC inputs are arranged so that two (or more) TADD-1 boards can be stacked, sharing common RF and DC inputs.
The TADD-Enclosure is available for this and other TADD kits ... Read more.
The complete kit is no longer available. You may purchase the bare PCB.
The price for the TADD-1 PCB only is:
$ 15 US for members of TAPR
$ 15 US for non-members+ shipping/handling if applicable.
Shipping and Handling
Shipping and Handling within the US will be by USPS Priority Mail.
International shipping costs are calculated as closely as possible. If the actual cost exceeds the estimate by more than $5.00, TAPR will contact you to get approval for the additional funds. TAPR uses insured Priority Mail International, unless the purchaser requires something else.
Assembly and Operations Manual
The assembly and operations manual can be found online at http://www.tapr.org/~n8ur/TADD-1_Manual.pdf.
TAPR kits can be complex depending on the kitting experience of each builder. We don't think you will have trouble with the kit, but it does require some knowledge and experience to successfully go from a kit to a finished, usable unit, depending on the mode of operations.
Questions concerning the construction and operation of the TADD-1 kit are discussed on the time-freq mailing list. To subscribe, click here.
The TAPR TADD-1 Kit was made possible by the efforts of:
John Ackermann, N8UR – Designer and Project Manager
Joe Borovetz, WA5VMS – Parts Liaison
Tom Van Baak – Performance Evaluation
Bob Leuchtner, WO6W – PCB Design Assistance
Tom Holmes, N8ZM
Daun Yeagley, N8ASB
Mike Suhar, WB8GXB
Bob Leuchtner, WO6W
Mike Feher, N4FS
Carl Walker, WA1RAJ
John Miles, KE5FX