Clifton Laboratories 7236 Clifton Road  Clifton VA 20124 tel: (703) 830 0368 fax: (703) 830 0711



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Z10024A Long Wave Low Pass Filter




The Z10024A is a receive-only 7th order elliptical low pass filter.

The filer can be supplied for various cutoff frequencies, with customer deliveries for 50 KHz, 140 KHz, 479 and 518 KHz having been made. The primary purpose of these filters is to reduce signals above the cutoff frequency, thereby improving reception. 




The photo below shows a Z10024A installed in an enclosure, with BNC connectors. (Top cover removed.)



Printed circuit board dimensions: 3.5 x 1.5 inches (88.9mm x 38.1mm)

Height: Approximately 1 inch (25mm)

Filter Type: 7th order elliptical.

Input and Output Impedance: 50 ohms

Cutoff Frequency: Consult Clifton Laboratories; with your requirements. Stock designs are available for 50, 140, 479 and 520 KHz and other frequencies can be custom designed.

Loss at Cutoff Frequency: Typical 3 dB

Ultimate Rejection: > 60 dB up to 30 MHz, typically > 80 dB in medium wave band

Input VSWR: Less than 3:1 < cutoff frequency.

Connectors: PCB has pads suitable for direct connection or 0.1� pin headers or SMA vertical mount connectors. When installed in enclosure, BNC, SMA, N and UHF connectors are available.

Power Rating: Receive only design. Recommended power level not to exceed +20 dBm.


Typical Performance Plots

520 KHz version

The plots below have a log horizontal axis, from 10 KHz to 30 MHz for a 520 KHz filter.

10 dB /Division. 


Expanded vertical scale, 1 dB/Division

50 KHz cutoff version; frequency response 1 KHz - 100 KHz. (below 3 KHz, the trace is hidden by the green graticule line.)

140 KHz cutoff version. Frequency response 100-300 KHz.


Pricing and Options

Pricing for the standard Z10024A Low Pass Filter is:

Assembled and tested, bare PCB for installation by the purchaser in his enclosure:


Assembled and tested, installed in an unpainted die cast enclosure with BNC connectors:


Optional swept measurement documentation (insertion and return loss) for an assembled filter or one built as a kit (plus return postage if an assembled kit is to be measured)


Domestic US shipping via Priority Mail is $7.50. Please contact Clifton Laboratories for international shipping.

If the Z10024A is to be shipped to a location within the Commonwealth of Virginia, please add 5% sales tax.

Enclosure Options:

Opt U: UHF connectors, silver/Teflon (import) with interior hoods: $12.50
Opt U*: UHF connectors, import, nickel plated, no hoods: $8.00 (Filter performance is not guaranteed with this option.)
Opt N: Type N connectors, with interior hoods $12.50
Opt S: SMA connectors. $12.50
Opt WSFL: Hammond 1590WSFL flanged weatherproof enclosure $14.00
Opt WSF: Hammond 1590WSF flanged weatherproof enclosure $18.00

The difference between Option WSFL and WSF is the flange location. Option WSFL has the flange on the enclosure lid and option WSF has the flange on the enclosure base. The weatherproof enclosure photograph at the top of the page is of the WSFL enclosure.

Options WSFL and WSF come with gasketed hardware - the 6-32 and 4-40 screws have recessed grooved heads with a Buna-S gasket to reduce water ingress.

These filters are assembled as orders arrive and most options will require an additional order interval. Normal order interval is one week.

Payment may be made with a check or money order payable to Clifton Laboratories at the address on the top of this page, or via PayPal to If ordering a filter, please also send a separate E-mail with your order specifics and contact information.