archived as http://www.stealthskater.com/Documents/PX_11.doc [.pdf](also …PX_11.pdf) => doc pdf URL-doc URL-pdf

more of the Philadelphia Experiment is at http://www.stealthskater.com/PX.htm

note: because important websites are frequently "here today but gone tomorrow", the following was archived on September 16, 2010. This is NOT an attempt to divert readers from the any websites. Indeed, the reader should only read this back-up copy if the updated original cannot be found at the original author's site.

details of the RCA "FRR-24" Receiver(allegedly used in the Montauk Project)

(an introduction is given in Chapter XIX of The Montauk Project: Experiments in Time archived at doc pdf URL )

http://online.sfsu.edu/~hl/AN_FRR-24.htmlhttp://userwww.sfsu.edu/~hl/kk6hy.html

National Radio Company's AN/FRR-24 HF Receiver Tuner Module(Model: Amplifier-Converter AM-450B/FRR-24)

--- the "Ultimate Big-Iron Receiver" ---

The 1950s' National AM-450B/FRR-24 is the tuner module of what is perhaps the most expensive, elaborate HF receiver ever manufactured in the United States. A complete receiver equipped for triple diversity monitoring (with all four RF modules for the full HF range of 2 to 32 MHz) contains a total of 420 vacuum tubes, weighs 3,121 pounds in four 6-foot rack cabinets, and sold for $60,000+ in 1947 dollars (or $581,000 adjusted for CPI inflation). It truly is a "Duesenberg" of radios and represents the very best of National Company's engineering talent.

I have only one of the 9-tube, 2-4 MHz tuner modules which includes 3 RF stages and separate mixer and oscillator tubes providing a 1750 kHz IF output for this double-conversion receiver. I would like to set it up for 80-meter operation with a homebrew power supply and IF amplifier/detector.

I am indebted to Nick England (K4NYW) for schematics and other documents and especially his expertise. If you can contribute any information to Nick regarding its development and historical use, I am sure he would love to hear from you. His website (which contains a treasure of photos and information about this receiver and other military models of interest to Nick) has the following URL:

http://www.navy-radio.com/rcvrs/frr24.htm

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AN/FRR-24 Receiver Front Panel

left interior right interior

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top view bottom view

close up of sealed 5-gang main tuning capacitor

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http://www.navy-radio.com/rcvrs/frr24.htm

National AN/FRR-24, AN/FRR-37, AN/FRR-42, AN/FRR-43, and AN/FRR-10 receivers

by Nick England (K4NYW)

If you have one of these monsters or any pieces of one, please send me an e-mail. I have acquired almost all the modules and cables to assemble a system and would like to acquire some additional pieces and information. I also have some spare modules to trade. I'd also like to correspond with other FRR-24, FRR-37, or FRR-10 owners as I start assembling and testing mine. I'd really like to hear from anyone who has photos or knows how&where these systems were used by the U.S. Navy.

AN/FRR-24 Triple-diversity HF AM/CW/FSK Receiver System

The AN/FRR-24 is a triple diversity dual-conversion HF (2-32 MC) receiver made by the National Co. (Malden, Mass.) around 1950. It was primarily designed for shore station teletype circuits. The operator's handbook 91580.2 and maintenance handbook 91580.3 that I have are dated 1952. The complete manual is NAVSHIPS 91580. Procured under contract NObsr-39402 (30 June 1947) for $60,260 ea.

Complete system as shown in manual

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The AN/FRR-24 consists of 4 racks weighing a total of 3,121 lbs. Racks 1, 2, and 3 contain essentially identical receiver assemblies. Each receiver rack has 4 RF tuning modules (2-4MC, 4-8MC, 8-16MC, 16-32MC). Each receiver rack also has a detector/AF unit for monitoring purposes. IF selectivity can be set from 18KC to 250cps bandwidth. Rack 4 contains 3 detectors and 3 FSK converters plus signal comparators for triple diversity reception. Rack 4 also has 3 keyers to drive TTY signals over landlines as audio FSK signals. See below for more info on the racks and all the modules. Each receiver rack has 88 vacuum tubes with 420 total for the entire system.

The system design is reasonably straightforward but extremely well-engineered and ruggedly-constructed. Each module is a 19" rack-mounted case with a slide-out, tilting chassis. Each RF module chassis is a massive aluminum casting with silver-plated tuning caps, etc. Co-ax and well-filtered power connections are made internally through a plug/jack block between chassis and case. Each case is fully enclosed with no external air access ( blowers at the base of each rack force cooling air around the sides of each module's case).

Rack 2 - upper Bandswitch + 4 RF units Rack 2 - lower 2nd mixer, detector/monitor,

IF amp, patch panel, bandpass filters, crystal oscillator, power supply

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left rack - misc storage National Company logo

Rack 2 - receiver unit #2

Typical Module Construction - AM-453 close-up of antenna, 3 RF,

AM-453 RF tuning module underside- and mixer stages with thorough shieldingmassive aluminum casting for chassis

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AM-453 close-up - cover for RF stages - Typical Module Construction -

grounding fingers plus. SB-142 "bandswitch" layout with individualthick silver-plated cover shield boxes for each switch section

SB-142 energizes a selected RF unit SB-142 close-up showing spring grounding

and routes HF oscillator and AGC lines clips for shields -- coax is fed from connectorto/from it rear under chassis and into shielded box.

SB-142 close up showing additional spring grounding fingers on shield7

My FRR-24 works!

With 3 RF units installed so far (11/06/2007)

<click> here for photos of my FRR-24 and FRR-37 systems undergoing re-assembly and restoration

There are 420 tubes in a complete AN/FRR-24. There are 88 tubes within each of the 3 receiver assemblies. Most RF and IF amp stages use type 9003 pentodes. For illustration, the main signal path of one receiver assembly (configured for AM reception) has over 20 tubes in the signal chain and is organized as follows:

● Bandswitch selects 1 of 4 RF units● 3 RF amp stages 6BA6 + 2x9003● 1st mixer (1750 kc IF out) 6BE6● 5 IF amp stages 5x9003● 2nd mixer (50 kc IF out) 6BE6● 1 IF amp stage 6C4● Bandwidth selects 1 of 8 filters (125 cycles to 18 kc) with 0-2 IF amp stages 9003 or 6AG5● 7 IF amp stages 3x9003 + 6C4 + 3x6AK6

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● detector 6AL5● AF amp 6BA6● AF output 6AK6

The AN/FRR-24 is exceptionally versatile. A set of patch panels allows the system to operate in different configurations. The Operator's manual lists 14 modes of operation and then says "these are but a few of the possible combinations of units".

For example, the system can operate as 3 separate receivers. Or it can combine outputs in dual or triple diversity mode. The 3 racks can be separately tuned or one of the receivers can be used as a master oscillator for the others or a separate crystal oscillator can drive one-or-more receivers. There are also multiple ways to couple AGC voltage among the units.

Module Rack 1 Rack 2 Rack 3 Rack 4A SB-142/FRR-24

Control PanelBand Switch

SB-142/FRR-24Control PanelBand Switch

SB-142/FRR-24Control PanelBand Switch

AM-440/FRR-24detectorAF + keyed DC out

B AM-450/FRR-242-4 mc RF1st converter1750 kc IF out

AM-450/FRR-242-4 mc RF1st converter1750 kc IF out

AM-450/FRR-242-4 mc RF1st converter1750 kc IF out

AM-440/FRR-24detectorAF + keyed DC out

C AM-451/FRR-244-8 mc RF1st converter1750 kc IF out

AM-451/FRR-244-8 mc RF1st converter1750 kc IF out

AM-451/FRR-244-8 mc RF1st converter1750 kc IF out

AM-438/FRR-24triple diversity detectorAF + keyed DC out

D AM-453/FRR-248-16 mc RF1st converter1750 kc IF out

AM-453/FRR-248-16 mc RF1st converter1750 kc IF out

AM-453/FRR-248-16 mc RF1st converter1750 kc IF out

CV-127/FRR-24FSK converterTTY output

E AM-452/FRR-2416-32 mc RF1st converter1750 kc IF out

AM-452/FRR-2416-32 mc RF1st converter1750 kc IF out

AM-452/FRR-2416-32 mc RF1st converter1750 kc IF out

CV-127/FRR-24FSK converterTTY output

F CV-126/FRR-242nd converter1750 kc IF in50 kc IF output

CV-126/FRR-242nd converter1750 kc IF in50 kc IF output

CV-126/FRR-242nd converter1750 kc IF in50 kc IF output

CV-127/FRR-24FSK converterTTY output

G AM-439/FRR-24MonitorDetector / AF out

AM-439/FRR-24MonitorDetector / AF out

AM-439/FRR-24MonitorDetector / AF out

KY-62/FRR-24TTY landline keyer

H AM-454/FRR-2450 kc IF amp

AM-454/FRR-2450 kc IF amp

AM-454/FRR-2450 kc IF amp

KY-62/FRR-24TTY landline keyer

J SB-138/FRR-24Patch Panel

SB-138/FRR-24Patch Panel

SB-138/FRR-24Patch Panel

KY-62/FRR-24TTY landline keyer

K F-99/FRR-2450 kc IF filters8 bandwidths

F-99/FRR-2450 kc IF filters8 bandwidths

F-99/FRR-2450 kc IF filters8 bandwidths

SB-143/FRR-24Patch Panel

L Tool Box O-131/FRR-24Oscillator

SB-141/FRR-24Power DistributionPanel

CM-32/FRR-24TTY Triple Diversity Comparator / Keyer

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M PP-590/FRR-24Power Supplyfor Rack 1

PP-590/FRR-24Power Supplyfor Rack 2

PP-590/FRR-24Power Supplyfor Rack 3

PP-649/FRR-24Power Supplyfor Rack 4

N PP-648/FRR-24Power Supplyfor Rack 4

If you have any additional info or parts for sale or trade, please let me know - nick@virhistory.com

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AN/FRR-37 Dual-diversity HF AM/CW/FSK Receiver System

The AN/FRR-37 is almost identical to the FRR-24 except with dual-diversity. The maintenance handbook (available from http://www.w7fg.com) is NAVSHIPS 91896.3 and dated March 1953. The complete manual is NAVSHIPS 91896. - MIL-HBK-161 (photo thanks to www.jamminpower.com). Procured under contract NObsr-57388 (21 May 1952) for $41,245 ea.

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The FRR-37 is a 3-rack dual-diversity version of the FRR-24 and is composed of racks 2, 3, and 4 (there is no rack 1). Rack 4 has 2 of various detector, converter, and keyer modules where the FRR-24 has 3 of them.

The FRR-37 rack (CY-1377/FRR-10) is about 12-14" deeper than the FRR-24 rack (CY-680/FRR-24), making cable access much easier. Almost all the FRR-37 modules have an 'A' suffix and are FRR-24 units as in SB-142A/FRR-24. However, some modules are slightly different with different unit numbers:

F-207/FRR-37 bandpass filter units for racks 2 and 3 (replaces F-99/FRR-24) SB-282/FRR-37 patch panel for rack 2 (replaces SB-140/FRR-24) SB-283/FRR-37 patch panel for rack 3 (replaces SB-169/FRR-24) SB-280/FRR-37 power distribution panel for rack 3 (replaces SB-141/FRR-24) SB-281/FRR-37 patch panel for rack 4 (replaces SB-143/FRR-24) PP-912/FRR-37 power supply for rack 4 lower replaces PP-648/FRR-24 PP-913/FRR-37 power supply for rack 4 upper replaces PP-649/FRR-24

Module Rack 2 Rack 3 Rack 4A SB-142A/FRR-24

Control PanelBand Switch

SB-142A/FRR-24Control PanelBand Switch

Blank

B AM-450A/FRR-242-4 mc RF1st converter1750 kc IF out

AM-450A/FRR-242-4 mc RF1st converter1750 kc IF out

AM-440A/FRR-24detectorAF + keyed DC out

C AM-451A/FRR-244-8 mc RF1st converter1750 kc IF out

AM-451A/FRR-244-8 mc RF1st converter1750 kc IF out

AM-438A/FRR-24dual diversity detectorAF + keyed DC out

D AM-453A/FRR-248-16 mc RF1st converter1750 kc IF out

AM-453A/FRR-248-16 mc RF1st converter1750 kc IF out

CV-127A/FRR-24FSK converterTTY output

E AM-452A/FRR-2416-32 mc RF1st converter1750 kc IF out

AM-452A/FRR-2416-32 mc RF1st converter1750 kc IF out

CV-127A/FRR-24FSK converterTTY output

F CV-126A/FRR-242nd converter1750 kc IF in50 kc IF output

CV-126A/FRR-242nd converter1750 kc IF in50 kc IF output

Tool Box

G AM-439A/FRR-24MonitorDetector / AF out

AM-439A/FRR-24MonitorDetector / AF out

KY-62A/FRR-24TTY landline keyer

H AM-454A/FRR-2450 kc IF amp

AM-454A/FRR-2450 kc IF amp

KY-62A/FRR-24TTY landline keyer

J SB-282/FRR-24Patch Panel

SB-283/FRR-24Patch Panel

SB-281/FRR-24Patch Panel

K F-207/FRR-3750 kc IF filters

F-207/FRR-3750 kc IF filters

CM-32A/FRR-24TTY Triple Diversity

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8 bandwidths 8 bandwidths Comparator / KeyerL O-131A/FRR-24

OscillatorSB-280/FRR-37Power DistributionPanel

PP-913/FRR-37Power Supplyfor Rack 4

M PP-590A/FRR-24Power Supplyfor Rack 2

PP-590A/FRR-24Power Supplyfor Rack 3

PP-912/FRR-37Power Supplyfor Rack 4

AN/FRR-10 Dual-diversity HF AM/SSB/ISB Receiver System

AN/FRR-10 System Circuit Description, Block Diagrams, & Configuration

The FRR-10 manual is NAVSHIPS 92144 dated 2 February 1954. The manual says it is basically the same as the predecessor receivers FRR-24 and FRR-37 except that the FRR-10 provides dual-diversity AM, SSB, and ISB (simultaneous LSB & USB) reception and does not provide FSK or CW capability. The shipping weight of a complete FRR-10 system is 3,740 lbs but the uncrated weight is a mere 2,362 lbs. The FRR-10 has 253 tubes and consumes about 1450 watts. Procured under contract number NObsr-52433 (23 May 1951) for $43,100 ea.

The FRR-10 is a 3-rack configuration containing 2 receiver racks for dual-diversity reception of AM, SSB, and ISB. It does not include FSK or CW capability. The receivers have the same 4 RF units and first converter as FRR-24 and FRR-37 but the 50kc IF amp, filters, detectors, AFC, and diversity control are all different and have /FRR-10 suffixes. IF selectivity is 8, 12, or 16kc plus USB and LSB filters. There is a motor-driven AFC control in Rack 3. Almost all the FRR-10 modules that are common to the FRR-24 have a 'B' suffix such AM-450B/FRR-24. However, for some reason the SB-142A/FRR-24 Control Panel is an exception.

The FRR-10 configuration uses the same rack cabinet (CY-1377/FRR-10) as the FRR-37.

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Module Rack 1 Rack 2 Rack 3A SB-142A/FRR-24

Control PanelBand Switch

SB-142A/FRR-24Control PanelBand Switch

F-171/FRR-10IF filter

B AM-450B/FRR-242-4 mc RF1st converter1750 kc IF out

AM-450B/FRR-242-4 mc RF1st converter1750 kc IF out

F-171/FRR-10IF filter

C AM-451B/FRR-244-8 mc RF1st converter1750 kc IF out

AM-451B/FRR-244-8 mc RF1st converter1750 kc IF out

AM-851/FRR-10RF amplifier

D AM-453B/FRR-248-16 mc RF1st converter1750 kc IF out

AM-453B/FRR-248-16 mc RF1st converter1750 kc IF out

CM-55/FRR-10signal comparator

E AM-452B/FRR-2416-32 mc RF1st converter1750 kc IF out

AM-452B/FRR-2416-32 mc RF1st converter1750 kc IF out

CM-49/FRR-10

F CV-126B/FRR-242nd converter1750 kc IF in50 kc IF output

CV-126B/FRR-242nd converter1750 kc IF in50 kc IF output

signal comparator

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G AM-900/FRR-1050 kc IF amp

AM-900/FRR-1050 kc IF amp

AM-722/FRR-10amp/detector

H SB-261/FRR-10patch panel

SB-260/FRR-10patch panel

ID-338/FRR-10AF monitor

J O-131B/FRR-24Oscillator

SB-253/FRRPower DistributionPanel

Tool Box

K Blank Blank PP-844/FRR-10Power Supplyfor Rack 3

L PP-884/FRR-10Power Supplyfor Rack 1

PP-884/FRR-10Power Supplyfor Rack 2

PP-844/FRR-10Power Supplyfor Rack 3

15

Circuit Description from 1960 ET2 Rate Training Manual NAVPERS 10190-B

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17

18

19

20

21

22

23

24

Installation drawing from FRR-10 manual

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AM-450B/FRR-24 info

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27

28

29

30

31

32

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AN/FRR-42 and AN/FRR-43 HF AM/CW Receiver Systems

System Description & Configuration Information The AN/FRR-42 is a 4-32 mc single channel, single-rack system similar to rack #2 of AN/FRR-24.

External equipment is necessary for FSK detection.

The AN/FRR-43 is a 4-32 mc 3-channel, 3-rack system similar to AN/FRR-24 but without the 4th rack. External equipment is necessary for diversity combining and FSK detection.

Manufactured by National - contract NObsr-57572 (19 June 1952)AN/FRR-42 - $18,025 ea. with equipment sparesAN/FRR-43 - $54,085 ea. with equipment sparesManual is NAVSHIPS 91891

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35

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Components

FRR-42 FRR-43 Module Purpose1 3 SB-142A/FRR-24 Bandswitch control panel1 3 AM-898/FRR RF amp & converter1 3 AM-452A/FRR-24 RF amp & converter1 3 AM-453A/FRR-24 RF amp & converter1 3 CV-277/FRR 2nd converter1 AM-857/FRR IF Amp & Detector1 3 AM-858/FRR IF Amp1 3 SB-232/FRR-42 Patch Panel- - SB-322/FRR-43 Patch Panel- 1 SB-321/FRR-43 Patch Panel- 1 SB-320/FRR-43 Patch Panel1 1 O-131A/FRR-24 Master Oscillator1 - SB-318/FRR-42 Power Distribution- 1 SB-319/FRR-43 Power Distribution1 3 PP-590A/FRR-24 Power Supply1 3 CY-1377/FRR-10 Cabinet

● Main Page - US Navy Radio info

● Info on US Navy Comm Stations

● Wanted Items - page 1

● Wanted Items - page 2

● Wanted items - page 3

● back to KD4CPL radio page

● Military Data Base Info (thanks to Bill NJ7P)

[StealthSkater note: In his Montauk books, Preston Nichols suggests the FRR-24 may have been "sent back in time" from 1983 Montauk for the 1943 Philadelphia Experiment => doc pdf URL . Also, some of this might have counter-intel uses such as alleged at doc pdf URL . I also wonder if the FRR-24 radios were capable of transmitting some sort of weird "white noise" that interfered with human consciousness and allowed Reality to be misrepresented (and hence not actual "time-travel). Makes one wonder about HAARP in Alaska.]

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http://jptronics.org/radios/Military/JANAP161/index.html

Directory of Communications-Electronic EquipmentJANAP 161, March 1953

I was most fortunate to obtain a copy of this huge document from Haney Howell a few years back and wanted to make it widely available -- and somewhat searchable --- by scanning each of the 1000-some pages and posting them to the web.

The organization of the document is explained in: Preface to JANAP 161

The AN/ nomenclature is described in Summary of AN Military Nomenclature System.

At present, all of the listings are in one huge table which you can search using the "find in page" (e.g., <Ctrl>F) function of your browser.

The table lists the AN/xxx number in the left column, and this entry is also the link to the PDF for each document. All documents are 2 pages, about 500KB. So, for example, <clicking> on ARC-5 in the first column brings up the document that describes this famous system of receivers.

In some cases the original Signal Corps or Navy designations are still used and the document lists these as AN/xxx-Type, then provides a Service Type Number (STN). So, for example, the listing for the SCR-522 is under ARC-Type (since it's an aircraft receiver) and the STN is "SCR-522".

Components are listed by AN/xxx-type followed by their complete nomenclature in the second column. For example, the "R-388" is AN/URR-type (1rst column) and R-388/URR (2nd column). Descriptions are exactly as listed in JANAP 161. Where there's information on the equivalent commercial product, it's listed in the last column.

In a few cases, there is no equipment unit designation, nor is there an STN. So these AN/xxx-type's refer to commercial equipment. The page for the Collins 18S-4 -- a commercial aircraft radio -- is an example.

Can't find the rig you're looking for? There are 2 possible explanations.

The radio or system wasn't in the military inventory as of March 1953. Refer to NJ7P's Military Equipment List to see when your rig was contracted.

The radio or system was classified like the AN/FRR-24 as was presumbly the rest of the equipment used in the "Philadelphia Experiment").

For those of you who'd like to print this document, here are the extra bits: Front Cover, Front Matter, Back Matter, Back Cover

Let me know if you think there's a more useful way to organize this material. Also let me know if you find any missing links or other errors.

… continued at => http://jptronics.org/radios/Military/JANAP161/index.html ...

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http://www.nj7p.org/cgi-bin/millist2?mode=normal&name=AN/FRR-24

Radio Receiving Set, AN/FRR-24

JAN Type: AN/FRR-24Nomenclature: Radio Receiving SetReference: NAVSHIPS 91580NSN: 5820-00-665-3514

Components: 3 ea AM-450/FRR-24 Amplifier-Converter, 3 ea AM-451/FRR-24 Amplifier-Converter, 3 ea AM-452/FRR-24 Amplifier-Converter, 3 ea AM-453/FRR-24 Amplifier-Converter, AM-438/FRR-24 Amplifier-Detector, 3 ea AM-438/FRR-24 Amplifier-Detector, 2 ea AM-438/FRR-24 Amplifier-Detector, 4 ea CY-680/FRR-24 Cabinet, CM-32/FRR-24 Comparator-Keyer, 3 ea SB-142/FRR-24 Control Panel, 3 ea F-99/FRR-24 Filter Assembly, 3 ea CV-126/FRR-24 Frequency Converter, 3 ea CV-127/FRR-24 Frequency Converter, 3 ea KY-62/FRR-24 Keyer, O-131/FRR-24 Oscillator Assembly, SB-138/FRR-24 Patch Panel, SB-140/FRR-24 Patch Panel, SB-143/FRR-24 Patch Panel, SB-169/FRR-24 Patch Panel, SB-141/FRR-24 Power Distribution Panel, 3 ea PP-590/FRR-24 Power Supply, PP-648/FRR-24 Power Supply, PP-649/FRR-24 Power Supply, 3 ea AM-454/FRR-24 RF Amplifier.

Weight: 4368

Size: 4 Equipment Racks

Mode: 0.1A1, 2A2, 6A3, 1.1F1, F4

Frequency Range: 2-32 MHz in 4 Bands

Power Input: 120 VAC 50-60 Hz 1.5 kW

Number of Channels: Variable or Crystal-Controlled

Part of: FRR-24

Description: Radio Receiving Set FRR-24 is a double-conversion superhetrodyne type diversity receiver for use at shore stations in point-to-point communication. It can receive signals in single-channel, space- or frequency-dual-, or triple-diversity operations such as double-sideband radiotelephone, on-off keyed radiotelegraph, and frequency- shift-keyed telegraph to operate single-channel teletypewriters at 24.5 dot cycles and/or up to 4-channel multiplex at 98 dot cycles.

The functions and performance of this equipment are similar to those of Radio Receiving Sets FRR-10 and FRR-37 except that the FRR-24 uses both dual- or triple-diversity operation and cannot receive single-sideband suppressed carrier signals. The complete equipment is contained in 4 rack cabinets permanently connected together.

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Source: TM 11-487A, 58Manufacturer: National Co., IncCost: 60,260.00Contract Year Manufacturer QuantityNObsr-39402 1947 National Co, Inc. ???

Created: Fri Apr 27 16:52:56 2001Last Modified: Fri Apr 27 17:14:17 2001

if on the Internet, press <BACK> on your browser to return to the previous page (or go to www.stealthskater.com)

else if accessing these files from the CD in a MS-Word session, simply <CLOSE> this file's window-session; the previous window-session should still remain 'active'

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