13D Filing: Gerst Capital, LLC and Microwave Filter Co Inc (MFCO)

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934
(Amendment No. ___________)

Microwave Filter Company, Inc.

(Name of Issuer)

Common stock, par value $.10 per share

(Title of Class of Securities)

595176108

(CUSIP Number)

Ellyn Roberts, Esq.
Shartsis Friese LLP
One Maritime Plaza, 18th Floor
San Francisco, CA 94111

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

January 25, 2018

(Date of Event Which Requires Filing of this
Statement)

If the filing person has previously filed a statement
on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of sections
240.13d-1(e), 240.13d-1(f) or 140.13d-1(g), check the following box. [ ]

Note: Schedules filed in paper format shall include
a signed original and five copies of the schedule, including all exhibits. See section 240.13d-7 for other parties to whom copies
are to be sent.

* The remainder of this cover page shall be filled out
for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent
amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover
page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”)
or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however,
see the Notes).

Potential persons who are to respond to the collection
of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

This statement relates to shares of Common stock, par value
$.10 per share (the “Stock”), of Microwave Filter Company, Inc. (the “Issuer”). The principal executive
office of the Issuer is located at 6743 Kinne Street, East Syracuse, NY 13057.

Item 2. Identity and Background

The persons filing this statement and the persons enumerated
in Instruction C of Schedule 13D and, where applicable, their respective places of organization, general partners, directors, executive
officers and controlling persons, and the information regarding them, are as follows:

The source and amount of funds used in purchasing the Stock
were as follows:

Gerst Capital purchased the Stock for investment purposes.

On January 29, 2018, Mr. Gerst sent a letter to the Issuer’s
board of directors informing them of his general agreement with the sentiments expressed in a letter dated January 19, 2018 to
the board from Zeff Capital, LP (“Zeff Capital”). Mr. Gerst’s letter also proposes that if the Issuer declines
to be purchased, the Issuer should invite Mr. Gerst to join the board as soon as practically possible. Although the Filers agree
with Zeff Capital, LP, they are not acting together with it or any other person or entity for the purpose of acquiring, holding,
voting or disposing of the Stock or any other securities. Accordingly, they do not believe that they are a group with any third
party within the meaning of Rule 13d-5 under the Act.

Otherwise, the Filers will routinely monitor the Issuer regarding
a wide variety of factors that affect their investment considerations, including, current and anticipated future trading prices
of the Stock and other securities, the Issuer’s operations, assets, prospects, financial position, and business development,
Issuer’s management, Issuer-related competitive and strategic matters, general economic, financial market and industry conditions,
and other investment considerations. Depending on their evaluation of various factors, including those in Mr. Gerst’s letter,
the Filers may take such actions regarding their holdings in the Issuer as they deem appropriate in light of circumstances existing
from time to time. Such actions may include purchasing additional Stock in the open market, through privately negotiated transactions
with third parties or otherwise, selling at any time, in the open market, through privately negotiated transactions with third
parties or otherwise, of all or part of the Stock now owned or hereafter acquired by either of them. The Filers also may from time
to time enter into or unwind hedging or other derivative transactions with respect to the Stock or pledge their interests in the
Stock to obtain liquidity. In addition, from time to time the Filers and their representatives and advisers may communicate with
other stockholders, industry participants and other interested parties about the Issuer. Further, the Filers may recommend action
to the Issuer’s management, board of directors and stockholders. Any of the foregoing actions could involve one or more of
the events referred to in paragraphs (a) through (j), inclusive, of Item 4 of Schedule 13D, including, potentially, one or more
mergers, consolidations, sales or acquisitions of assets, change in control, issuances, purchases, dispositions or pledges of securities
or other changes in capitalization.

The beneficial ownership of the Stock by each Filer on the
date hereof is reflected on that Filer’s cover page.

The Filers effected no transactions in the Stock in the 60
days before the date on cover page.

None.

Exhibit A Agreement Regarding Joint Filing of Statement
on Schedule 13D or 13G.

Exhibit B Letter dated January 29, 2018 from Gerst Capital
to the Issuer’s board of directors.

SIGNATURES

After reasonable inquiry and to the best of my knowledge, I certify
that the information set forth in this statement is true, complete and correct.

Dated: __________________

EXHIBIT A

AGREEMENT REGARDING JOINT FILING

OF STATEMENT ON SCHEDULE 13D OR 13G

The undersigned agree to file jointly with the Securities and Exchange
Commission (the “SEC”) any and all statements on Schedule 13D, Schedule 13G or forms 3, 4 or 5 (and any amendments
or supplements thereto) required under section 13(d) or 16(a) of the Securities Exchange Act of 1934, as amended, in connection
with purchases by the undersigned of the securities of any issuer. For that purpose, the undersigned hereby constitute and appoint
Gerst Capital, LLC, a Delaware limited liability company, as their true and lawful agent and attorney-in-fact, with full power
and authority for and on behalf of the undersigned to prepare or cause to be prepared, sign, file with the SEC and furnish to any
other person all certificates, instruments, agreements and documents necessary to comply with section 13(d) and section 16(a) of
the Act, in connection with said purchases, and to do and perform every act necessary and proper to be done incident to the exercise
of the foregoing power, as fully as the undersigned might or could do if personally present.

Dated: __________________

EXHIBIT B

January 29, 2018

Board of Directors

c/o Robert Andrews, Chairman

Microwave Filter Company, Inc.

6743 Kinne Street

East Syracuse, NY 13057

Dear Mr. Andrews,

I generally agree with the sentiments expressed in Zeff
Capital’s letter dated January 19, 2018.

If the company decides not to pursue Mr. Zeff’s
offer, then it is long past time for the board to include outsiders with material “skin in the game”. If the company
declines to be purchased, I propose that I be invited to join the board of directors as soon as practically possible.

My technical background, wireless industry experience, and financial expertise qualify me to become an effective, active and contributing
member of Microwave Filter Company’s board.

Regards,

Greg Gerst, CFA