Fair Radio Sales Surplus Macom 16179/3001-4033-00 Dummy Load

I got one of Fair Radio Sales surplus FAA-DUMMY dummy loads. It came marked Macom 16179 and 3001-4033-00, which is essentially unfindable. Presumably those are internal or customer part numbers for the component in its original application. Anyways, what is it and what's inside?

Overview of the load with an additional N-to-BNC bulkhead adapter

The above adapter is also from Fair Radio Sales, the UG-606 N female jack to bulkhead BNC female jack, removed from FAA equipment. Quite possibly the same set of assemblies as the load! Just right for mating to my cables for typical load use.

Came with free mounting hardware not pictured in the product listing. Given the lack of paste residue, presumably not used for substantial thermal link to the original equipment.

The connector assembly connects easily with four screws and matching lock-washers.

The interesting view: inside the flange connector to the resistive element and its connection to the overall block. Nice stainless RF path set into the aluminum.

The matching flange has a teflon socket with a pin hiding up inside on the coax. Retention screws on the side.

The coax to the N male plug is HARBOUR INDUSTRIES MIL-C-17/60C M17/60-RG-142 27478. Connector to flange length of about 8 inches.

Not pictured, throwing the load on my nanoVNA shows that it's nice and flat to the capabilities of the unit through 900 MHz, eventually (see below). Corresponds well to being intended for VHF/UHF equipment. Definitely would be decent to see what the 4.4 GHz v2 edition would say about it. Ohms out decently to about 50 at DC, plus resistance from cables and adapters.

Addendum: lessons in RF testing. The easiest way to start testing this was a different N to BNC adapter to connect to the pigtail that lives on my nanoVNA and to BNC to banana for going to the DMM. Initial SWR trace was horrid and DC ohms was showing various kiloohms, definitely not 50. Turns out, the center contact pin of the BNC side was covered in corrosion products from the adapter being very well aged kinda-NOS, not in a bag. Some friction cleaning got the tarnished silver a bit more exposed and it started working again. Just took comparing against a known-good commercial N 50 ohm termination to establish where in the chain things were messed up.

 

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