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Proc-Type: 2001,MIC-CLEAR
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<SEC-DOCUMENT>0000315066-99-000142.txt : 19990211
<SEC-HEADER>0000315066-99-000142.hdr.sgml : 19990211
ACCESSION NUMBER:		0000315066-99-000142
CONFORMED SUBMISSION TYPE:	SC 13G
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		19990210

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALPHA INDUSTRIES INC
		CENTRAL INDEX KEY:			0000004127
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				042302115
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	FILING VALUES:
		FORM TYPE:		SC 13G
		SEC ACT:		
		SEC FILE NUMBER:	005-34048
		FILM NUMBER:		99528668

	BUSINESS ADDRESS:	
		STREET 1:		20 SYLVAN RD
		CITY:			WOBURN
		STATE:			MA
		ZIP:			01801
		BUSINESS PHONE:		6179355150

	MAIL ADDRESS:	
		STREET 1:		20 SYLVAN RD
		STREET 2:		20 SYLVAN RD
		CITY:			WOBURN
		STATE:			MA
		ZIP:			01801

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FMR CORP
		CENTRAL INDEX KEY:			0000315066
		STANDARD INDUSTRIAL CLASSIFICATION:	UNKNOWN SIC - 0000 [0000]
		IRS NUMBER:				161144965
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G

	BUSINESS ADDRESS:	
		STREET 1:		82 DEVONSHIRE ST
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02109
		BUSINESS PHONE:		6175706339

	MAIL ADDRESS:	
		STREET 1:		82 DEVONSHIRE STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02109
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G
<SEQUENCE>1
<DESCRIPTION>SCHEDULE 13G - 02-01-99 - ALPHA INDUSTRIES INCORPORATED
<TEXT>


SCHEDULE 13G

Amendment No. 0 
Alpha Industries Incorporated 
common stock 
Cusip # 020753109                

Cusip # 020753109           
Item 1:	Reporting Person - FMR Corp.
Item 4:	Commonwealth of Massachusetts
Item 5:	7,400 
Item 6:	0 
Item 7:	973,400 
Item 8:	0 
Item 9:	973,400 
Item 11:	9.234% 
Item 12:	    HC

Cusip # 020753109    
Item 1:	Reporting Person - Edward C. Johnson 3d 
Item 4:	United States of America
Item 5:	0 
Item 6:	0 
Item 7:	973,400 
Item 8:	0 
Item 9:	973,400 
Item 11:	9.234% 
Item 12:	IN 

Cusip # 020753109      
Item 1:	Reporting Person - Abigail P. Johnson 
Item 4:	United States of America
Item 5:	None 
Item 6:	None 
Item 7:	973,400 
Item 8:	None 
Item 9:	973,400 
Item 11:	9.234% 
Item 12:	    IN


SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS
FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b)


Item 1(a).	Name of Issuer:	

		Alpha Industries Incorporated 

Item 1(b).	Name of Issuer's Principal Executive Offices:

		20 Sylvan Road 
		Woburn, MA  01801  

Item 2(a).	Name of Person Filing: 

		FMR Corp.

Item 2(b).	Address or Principal Business Office or, if None, 
Residence:

		82 Devonshire Street, Boston, Massachusetts  02109

Item 2(c).	Citizenship:

		Not applicable

Item 2(d).	Title of Class of Securities:

		common stock 

Item 2(e).	CUSIP Number:  

		020753109 

Item 3.	This statement is filed pursuant to Rule 13d-1(b) or 13d-
2(b) and the person filing, FMR Corp., is a parent holding company in 
accordance with Section 240.13d-1(b)(ii)(G).  (Note:  See Item 7).

Item 4.	Ownership

	(a)	Amount Beneficially Owned:	973,400 

	(b)	Percent of Class:	9.234% 

	(c)	Number of shares as to which such person has:  

	(i)	sole power to vote or to direct the vote:	7,400 

	(ii)	shared power to vote or to direct the vote:	0 

	(iii)	sole power to dispose or to direct the disposition of:
	973,400 

	(iv)	shared power to dispose or to direct the disposition of:
	0 




Item 5.	Ownership of Five Percent or Less of a CommonStock.

	Not applicable.

Item 6.	Ownership of More than Five Percent on Behalf of Another 
Person.

	Various persons have the right to receive or the power to direct 
the receipt of dividends from, or the proceeds from the sale of, the 
common stock of Alpha Industries Incorporated.  No one person's 
interest in the common stock of Alpha Industries Incorporated is more 
than five percent of the total outstanding common stock.

Item 7.	Identification and Classification of the Subsidiary Which 
Acquired the Security Being Reported on By the Parent Holding Company.

	See attached Exhibit(s) A, B. 

Item 8.	Identification and Classification of Members of the Group.

	Not Applicable. See attached Exhibit A. 

Item 9.	Notice of Dissolution of Group.

	Not applicable.

Item 10.	Certification.

	By signing below I certify that, to the best of my knowledge and 
belief, the securities referred to above were acquired in the ordinary 
course of business and were not acquired for the purpose of and do not 
have the effect of changing or influencing the control of the issuer of 
such securities and were not acquired in connection with or as a 
participant in any transaction having such purpose or effect.

	
Signature

	After reasonable inquiry and to the best of my knowledge and 
belief, I certify that the information set forth in this Schedule 13G 
in connection with FMR Corp.'s beneficial ownership of the common stock 
of Alpha Industries Incorporated at December 31, 1998 is true, complete 
and correct. 


	February 01, 1999 
Date



	/s/Eric D. Roiter
Signature



	Eric D. Roiter	
	Duly authorized under Power of Attorney
	dated December 30, 1997, by and on behalf
	of FMR Corp. and its direct and indirect
	subsidiaries



SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS
FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b)

	Pursuant to the instructions in Item 7 of Schedule 13G, Fidelity 
Management & Research Company ("Fidelity"), 82 Devonshire Street, 
Boston, Massachusetts 02109, a wholly-owned subsidiary of FMR Corp. and 
an investment adviser registered under Section 203 of the Investment 
Advisers Act of 1940, is the beneficial owner of 966,000 shares or 
9.164% of the common stock outstanding of Alpha Industries Incorporated  
("the Company") as a result of acting as investment adviser to various 
investment companies registered under Section 8 of the Investment 
Company Act of 1940.

	Edward C. Johnson 3d, FMR Corp., through its control of Fidelity, 
and the funds each has sole power to dispose of the 966,000 shares 
owned by the Funds.

	Neither FMR Corp. nor Edward C. Johnson 3d, Chairman of FMR 
Corp., has the sole power to vote or direct the voting of the shares 
owned directly by the Fidelity Funds, which power resides with the 
Funds' Boards of Trustees.  Fidelity carries out the voting of the 
shares under written guidelines established by the Funds' Boards of 
Trustees.

	Fidelity Management Trust Company, 82 Devonshire Street, Boston, 
Massachusetts 02109, a wholly-owned subsidiary of FMR Corp. and a bank 
as defined in Section 3(a)(6) of the Securities Exchange Act of 1934, 
is the beneficial owner of  7,400 shares or 0.070% of the common stock 
outstanding of the Company as a result of its serving as investment 
manager of the institutional account(s). 

	Edward C. Johnson 3d and FMR Corp., through its control of 
Fidelity Management Trust Company, each has sole dispositive power over 
7,400 shares and sole power to vote or to direct the voting of 7,400 
shares of common stock owned by the institutional account(s) as 
reported above.

	Members of the Edward C. Johnson 3d family and trusts for their 
benefit are the predominant owners of Class B shares of common stock of 
FMR Corp., representing approximately 49% of the voting power of FMR 
Corp.  Mr. Johnson 3d owns 12.0% and Abigail Johnson owns 24.5% of the 
aggregate outstanding voting stock of FMR Corp.  Mr. Johnson 3d is 
Chairman of FMR Corp. and Abigail P. Johnson is a Director of FMR Corp.  
The Johnson family group and all other Class B shareholders have 
entered into a shareholders' voting agreement under which all Class B 
shares will be voted in accordance with the majority vote of Class B 
shares.  Accordingly, through their ownership of voting common stock 
and the execution of the shareholders' voting agreement, members of the 
Johnson family may be deemed, under the Investment Company Act of 1940, 
to form a controlling group with respect to FMR Corp.


 .


SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS
FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b)
RULE 13d-1(f)(1)  AGREEMENT

	The undersigned persons, on February 01, 1999, agree and consent 
to the joint filing on their behalf of this Schedule 13G in connection 
with their beneficial ownership of the common stock of Alpha Industries 
Incorporated at December 31, 1998.

FMR Corp.

By   /s/Eric D. Roiter   			
	Eric D. Roiter
	Duly authorized under Power of Attorney
	dated December 30, 1997, by and on behalf
	of FMR Corp. and its direct and indirect 
	subsidiaries

Edward C. Johnson 3d

By   /s/Eric D. Roiter   			
	Eric D. Roiter
	Duly authorized under Power of Attorney
	dated December 30, 1997, by and on behalf
	of Edward C. Johnson 3d

Abigail P. Johnson

By   /s/Eric D. Roiter   			
	Eric D. Roiter
	Duly authorized under Power of Attorney
	dated December 30, 1997, by and on behalf
	of Abigail P. Johnson

Fidelity Management & Research Company

By   /s/Eric D. Roiter   			
	Eric D. Roiter
	V.P. and General Counsel






</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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