Navy HF Diversity Receiving Systems

Diversity systems use 2 or 3 receivers to copy the same traffic (typically CW or RTTY) from one or more transmitters
Frequency diversity - receivers tuned to different frequencies - to cover shifting ionospheric propagation
Spatial diversity - receivers tuned to the same frequency but connected to different antennas - to cover fading and multipath

Back to Main Receiver Page
Back to main Navy Radio Page
Please send me e-mail if you have any additions, corrections, etc.

HF Diversity Receiver Systems
model	type	primary use	freq	features
AN/FRR-3 AN/FRR-3A		Dual Diversity 2.4-23 mc HF Shore FSK Remote dial-up to select 5 fixed frequencies and 4 antenna combinations		manuf Press Wireless TM 11-872
AN/FRR-10		Dual Diversity HF shore SSB (simultaneous USB & LSB) variant of FRR-24 click here for info	2-32 mc	dual diversity 253 tubes Manuf National info
AN/FRR-24		Triple Diversity HF shore RTTY & CW click here for info	2-32 mc	triple diversity 420 tubes Manuf National info/photos
AN/FRR-28	two R-450/FRR-28 rcvrs O-165/UR master oscillator AM-615/UR amplifier/detector KY-79/UR keyer SB-224/UR patching panel LS-187/UR speaker	R-450/FRR-28 showing AVC switch and ID tags	0.54-54 mc Dual Diversity - HF shore More R-450/FRR-28 photos used with AN/URA-8A RTTY converter FRR-28 at NAVCOMMSTA Kodiak 1959	uses two Hammarlund SP-600-MX (R-450/FRR-28) manuf - Northern Radio info SP-600 manuals FRR-28 spec sheet - page 1 FRR-28 spec sheet - page 2 Manual - NAVSHIPS 91582 (available from Andy Moorer)
AN/FRR-32			Dual Diversity - HF shore system 2-32mc two R-618/FRR-32 rcvrs (probably modified FRR-23) O-330/FRR-32 master xtal oscillator CM-70/FRR-32 comparator/keyer SB-431/FRR-32 patching panel LS-169/G speaker CY-597A/G rack	Manuf RCA NAVSHIPS 92736
AN/FRR-37		Dual Diversity version of FRR-24 HF shore RTTY & CW Click here for component info	2-32 mc	dual diversity approx 250 tubes Manuf National info/photos
AN/FRR-38		Dual Diversity FSK two R-390(*) receivers CV-116/URR dual FSK converter	0.5-32 mc FRR-38 and FRR-41 at NAVRADSTA ( R) Salinas	Signal Corps procurement but used by USN Manuf Collins & Hoffman TM-11-647 TO: 31R2-2FRR38, 31R-1-8
AN/FRR-41		Dual diversity SSB two R-390(*) receivers two CV-157 SSB converters (simultaneous USB & LSB from each)	0.5-32 mc FRR-38 and FRR-41 at NAVRADSTA (R) Salinas	Signal Corps procurement but used by USN Manuf Collins & others TM 11-649 TO: 31R2-2FRR-221
AN/FRR-42 AN/FRR-43	Subset of AN/FRR-24	Click Here for Info	-	-
AN/FRR-51	need photo	Dual-diversity HF with 10 channel auto-tune R-792/URR receiver (2 ea.) CU-560/URR antenna coupler C-2087/URR receiver control C-2086/URR remote switching control CV-116/URR FSK converter CV-395/U Signal Data Converter CY-1119/U cabinet	need info	need info - please send e-mail
AN/FRR-60	photo from TMC vintage radio web site	HF shore diversity system NAVCOMMSTA Guam - 1960's	info needed	Info - AN/FRR-60 Page Manuf TMC Model DDR-5
AN/FRR-64	need photos	TMC DDR-10	-	-
AN/URR-49	Guam 1968 - URR-49 configurations	HF shipboard/shore FSK dual-diversity system two R-390A receivers AN/URA-8A dual FSK converter	info needed	Nomenclature was assigned and configuration was widely used, but I'm not sure it was ever procured as URR-49
RAE	Pre-war triple-diversity HF unit using three RAB receivers	See RAB photos and info on WW2 Receiver Page	-	-
RBP RBP-1 RCP			1940's system 3-24 mc RBP is dual triple-diversity system (6 rcvrs) RCP is single triple-diversity system (3 rcvrs)	Manuf RCA RBP & RCP Page - spec sheets, photos, and downloadable manual
RDM (RCA DR-89)	Triple Diversity HF System using RCA AR-88 receivers		CRV-46246-A (RCA-AR-88F) as used in RDM	CRV-46246-B (RCA CR-88) as used in RDM-1 Manual NAVSHIPS 91061 Download 28.9 MB pdf More info coming soon.
RDM (RCA DR-89)