AN-URM-25B_RF_signal_generator_serv_user_TM11-5551B_1954.pdf

TM 11-5551B DEPARTMENT OF THE ARMY TECHNICAL MANUAL R. F. SIGNAL GENERATOR SET AN/URM-25B This copy is a reprint which includes current pages from change 1. DEPARTMENT OF THE ARMY JANUARY 1954 TM 11-5551B C 1 R. F. SIGNAL GENERATOR SET AN/URM-25B CHANGEHEADQUARTERS DEPARTMENT OF THE ARMY No. 1WASHINGTON, D.C., 19 November 1963 TM 11-5551B, 25 January 1954, is changed as follows: Page 1-1. Add paragraphs 1.1 and 1.2 after paragraph 1. 1.1. Index of Publications Refer to the latest issue of DA Pam 310-4 to determine whether there are new editions, changes or additional publications pertaining to the equipment. DA Pam 3104 is an index of current technical manuals, technical bulletins, Supply manuals (types 4, 6, 7, 8, and 9), supply bulletins, lubrication orders, and modification work orders available through publications supply channels. The index lists the individual parts (-10, -20, -35P, etc) and the latest changes to and revisions of each equipment publication. 1.2. Forms and Records aReports of Maintenance and Unsatisfactory Equipment. Use equipment forms and records in accordance with instructions in TM 38-750. bReport of Damaged or Improper Shipment.Fill out and forward DD Form 6 (Report of Damaged or Improper Shipment) as prescribed in AR 700-58 (Army), NAVASANDA Publication 378 (Navy), and AFR 71-4 (Air Force). cReporting of Equipment Manual Improvements. The direct reporting by the individual user of errors, omissions, and recommendations for improving this manual is authorized and encouraged. DA Form 2028 (Recommended changes to DA technical manual parts lists or supply manual 7, 8, or 9) will be used for reporting these improvements. This form will be completed in triplicate using pencil, pen, or typewriter. The original and one copy will be forwarded direct to Commanding Officer, U. S. Army Electronics Material Support Agency, ATTN: SELMS-MP, Fort Monmouth, N. J. 07703. One information copy will be furnished to the individuals immediate supervisor (officer, noncommissioned officer, supervisor, etc). Page 5-1. Delete paragraph 1 and substitute: 1. Scope of Maintenance The maintenance duties assigned to the operator and organizational repairman of the equipment are listed below together with a reference to the paragraphs covering the specific maintenance functions. aDaily preventive maintenance checks and services (par. 1.3). bWeekly preventive maintenance checks and services (par. 1.4). cMonthly preventive maintenance checks and services (par. 1.5). dQuarterly preventive maintenance checks and services (par. 1.6). eCleaning (par. 1.7). fTouchup painting (par. 1.8). gRoutine check (table 5-1). Add paragraphs 1.1 through 1.8 after paragraph 1. 1.1. Preventive Maintenance Preventive maintenance is the systematic care, servicing, and inspection of equipment to prevent the occurrence of trouble, to reduce downtime, and to assure that the equipment is serviceable. aSystematic Care. The procedures given in paragraphs 1.3 through 1.7 cover routine systematic care and cleaning essential to proper upkeep and operation of the equipment. b.Preventive Maintenance Checks and Services. The preventive maintenance checks and services charts (par. 1.3- 1.6) outline functions to be performed at specific intervals. These checks and services are to maintain Army electronic equipment in a combat serviceable condition; that is, in good general (physical) condition and in good operating condition. To assist operators in maintaining combat serviceability, the charts indicate what to check, how to check, and what the normal conditions are; the references column lists the tables or manuals that contain detailed repair or 1 replacement procedures. If the defect cannot be remedied by performing the corrective actions listed, higher echelon maintenance or repair is required. Records and reports of these checks and services must be made in accordance with the requirements set forth in TM 38-750. 1.2. Preventive Maintenance Checks and Services Periods Preventive maintenance checks and services of the equipment are required daily, weekly, monthly and quarterly. aParagraph 1.3 specifies the checks and services that must be accomplished daily (or at least once each week if the equipment is maintained in standby condition). b.Paragraphs 1.4, 1.5, and 1.6 specify additional checks and services that must be performed on a weekly, monthly, and quarterly basis, respectively. 1.3. Daily Preventive Maintenance Checks and Services Chart Sequence No. ItemProcedureReferences 1Completness.See that the equipment is complete.Table 1-1 2Exterior surface.Clean the exterior surfaces, including the panel, dial windows, and meter glass (par. 1.7). Check all glass and indicator lens for cracks. 3Connectors.Check the tightness of all connectors 4Controls and indicators.While making the operating checks (item 5), observe that the mechanical action of each knob, dial, and switch is smooth and free of external or internal binding, and that there is no excessive looseness. Also, check the meter for sticking or bent pointer. 5Operation.Operate the equipment according to table 5-1.Table 5-1 1.4. Weekly Preventive Maintenance Checks and Services Chart Sequence No. ItemProcedureReferences 1Cables.Inspect or, cables and wires for chafed, cracked, or frayed insulation. Replace connectors that are broken, arced, stripped, or worn excessively. None 2Handles and latch.Inspect handles and latches for looseness. Replace or tighten as necessary. None 3Metal surfaces.Inspect exposed metal surfaces for rust and corrosion. Touchup paint as required (par. 1.8). None 1.5. Monthly Preventive Maintenance Checks and Services Chart Sequence No. ItemProcedureReferences 1Pluckout items.Inspect seating of pluckout items. Make certain that tube clamps grip tube bases tightly None 2Jacks .Inspect jacks for snug fir and good contact.None 3Transformer terminals.Inspect the terminals on the power transformer. All nuts must be tight. There should be no evidence of dirt or corrosion. None 4Terminal blocks.Inspect terminal blocks for loose connections and cracked of broken insulation None 5Resistors and capacitors .Inspect the resistors and capacitors for cracks, blistering, or other determental defects None 6Gaskets and insulators.Inspect gaskets, insulators, bushings, and sleeves for cracks, chipping, and excessive wear. None 7Variable capacitors.Inspect variable capacitors for dirt, corrosion and deformed plates.None 8InteriorClean interior of chassis and cabinet .None 2 1.6. Quarterly Preventive Maintenance Checks and Services Chart Sequence No. ItemProcedureReferences 1Publications .See that all publications are complete, serviceable, and currentDA Pam 310-4 2Modifications.Check DA Pam 310-4 to determine if new applicable MWOs have been published. All urgent MWOs must be applied immediately. All normal MWOs must be scheduled. TM 38-750 1.7. Cleaning Inspect the exterior of the equipment. The exterior surfaces should be clean, and free of dust, dirt, grease, and fungus. aRemove dust and loose dirt with a clean soft cloth. Warning: Cleaning compound is flammable and its fumes are toxic. Provide adequate ventilation Do not use near a flame. bRemove grease, fungus, and ground-in dirt from the case; use a cloth dampened (not wet) with cleaning compound (Federal stock No. 7930-395-9542). cRemove dust or dirt from plugs and jacks with a brush. Caution: Do not press on the dial windows or meter face (glass) when cleaning; the dial windows and meter may become damaged. dClean .he front panel, dial windows, meter, and control knobs; use a soft clean cloth. If necessary, dampen the cloth with water; mild soap may be used for more effective cleaning. 1.8. Touchup Painting Instructions Remove rust and corrosion from metal surfaces by lightly sanding them with fine sandpaper. Brush two thin coats of paint on the bare metal to protect it from further corrosion. Refer to the applicable cleaning and refinishing practices specified in TM 9-213. Page 7-0. Delete section 7 and substitute the following appendix: APPENDIX REFERENCES DA Pam 310-4Index of Technical Manuals, Technical Bulletins, Supply Manuals (types 4, 6, 7, and 9) Supply Bulletins, Lubrication Orders, and Modification Work Orders. TM 9-213Painting Instructions for Field Use. TM 11-5527Multimeters TS-352/U, TS- 352A/U, and TS-352B/U. TM 38-750The Army Equipment Record System and Procedures. 3 By Order of the Secretary of the Army: EARLE G. WHEELER, General, United States Army, Official:Chief of Staff. J. C. LAMBERT, Major General, United States Army, The Adjutant General. Distribution: Active Army: DASA (6)Sig Dep (OS) (12) USASA (2)GENDEP (OS) (2) CNGB (1)Sig Sec, GENDEP (OS) (5) CSigO (7)USA Trans Tml Comd (1) CoflT (1)Army Tml (1) CofEngrs (1)USASCC (4) TSG (1)USAECDA (1) Cofspt Svcs (1)USACBRCDA (2) USAARMBD (2)USACECDA (2) USAIB (2)USAMSCDA (1) USARADBD (2)USAOCDA (1) USAATBD (2)USAQMCDA (1) USAAESWBD (2)USATCDA (1) USAMC (5)USAADCDA (1) USCONARC (5)USAARMCDA (1) ARADCOM (2)USAAVNCDA (1) ARADCOM Rgn (2)USAARTYCDA (1) OS Maj Comd (3)USASWCDA (2) OS Base Comd (2)USAOSA (1) LOGCOMD (2)USA Elct Mat Agcy (25) USAECOM (7)USARSOUTHCOM Sig Agcy (1) USAMICOM (4)White House Army Comm Agcy (2) MDW (1)WRAMC (1) Armies (2)Army Pic Cen (2) Corps (2)USA Mob Spt Cen (1) USA Corps (3)USARPRDC (2) 1st FA Mal Bde (2)USA Sp Warfare Cen (2) Instl (2) exceptUSACDEC (2) Ft Monmouth (63)Chicago Proc Dist (1) Ft Lee (5)AMS (1) Ft Holabird (5)APP (1) USMA (2)USA Engr RD Agcy (Pt Huachuca) (2) Svc Colleges (2)USA Engr RD Agcy (White Sands) (18) Br Svc Sch (2) exceptUSAERDL (2) ARADSCH (5)USASATSA (2) USATC FA (8)POE (1) USATC AD (2)Sig Fld Maint Shops (3) USATC Armor (2)Yuma PG (2) USATC Engr (2)WSMR (5) USATC Inf (3)USARMIS: Venezuela (2) USATC (2)Paraguay, Ecuador (2) Army Dep (2) exceptJUSMMAT (2) Lexington (12)Edgewood Arsenal (5) Sacramento (28)Jefferson PG (2) Tobyhanna (12)USAEPG (2) Ft Worth (8)USAMTMSA (2) Granite City (5)MAAG Iran (2) Columbus (5)ARMIS (2) Letterkenney (5)GENMIS (2) Utah (5)KMAG (2) NG: State AG (3); Div (1). USAR: None. For explanation of abbreviations used, see AR 320-50. 4 TM 11-5551B TECHNICAL MANUAL DEPARTMENT OF THE ARMY No. 11-5551B WASHINGTON 25, D. C., 25 January 1954 R. F. SIGNAL GENERATOR SET AN/URM-25B SECTION 1 - GENERAL DESCRIPTION Paragraph Page 1. Introduction .1-1 2. Reference Data .1-1 3. Detailed Description.1-1 4. Electron Tube Complement .1-2 5. Similarities Between Equipments .1-3 SECTION 2 - THEORY OF OPERATION 1. General Description of Circuits .2-0 2. Carrier Oscillator .2-1 3. Buffer-Amplifier.2-2 4. Modulation Oscillator .2-3 5. Electron Tube Voltmeter .2-4 a. RF Diode .2-4 b. Modulation Diode .2-5 c. Voltmeter Bridge Circuit .2-6 d. Voltmeter Bridge Adjustments.2-6 6. Variable RF Attenuator 7. Crystal Calibrator.2-9 8. Terminating the Signal Generator .2-9 9. (5:1) Fixed Attenuator CN-132/URM-25.2-11 10.( 10:1) Fixed Attenuator CN-136/URM-25.2-11 11.Antenna Simulator SM-35/URM-25 .2-12 12.Test Lead CX-1363/U .2-12 13.Power Supply PP-562A/URM-25 .2-12 14.Incidental Frequency Modulation .2-14 SECTION 3 - INSTALLATION 1. Unpacking .3-0 2. Installation.3-1 3. Adjustments .3-1 SECTION 4 - OPERATION 1. General .4-0 2. Power Circuit.4-1 3. Calibrating the Electron Tube Voltmeter.4- 4. Adjusting Carrier Frequency .4-2 5. Crystal Calibrator .4-2 6. Adjusting Output Voltage.4-3 7. Internal Modulation .4-4 8. External Modulation.4-4 9. Coupling to the Receiver Under Test.4-4 a. x Mult RF Output Jack (J102) .4-4 b. x 20, 000 RF Output Jack (J101) .4-4 10.Use of Antenna Simulator SM-35/URM-25.4-5 12.Use of (10:1) Fixed Attenuator CN-1369-/URM-25.4-6 13. Summary of Operation 4-7 Paragraph Page 14.General Instructions for Use . 4-7 a. Details. 4-7 b. Receiver Tests . 4-7 c. Modulated Operation . 4-8 d. Receiver Output. 4-8 e. Receiver Overall Sensitivity . 4-8 f. Standard Antenna Electrical Constants. 4-8 g. Standard Levels . 4-8 h. Voltmeter Used as an Output Meter . 4-8 SECTION 5 - PREVENTIVE MAINTENANCE 1. Routine Maintenance Check Chart. 5-1 2. Fuse Failure . 5-1 3. Lubrication . 5-1 SECTION 6 - CORRECTIVE MAINTENANCE 1. General . 6-1 2. Principal Maintenance Problems. 6-1 3. Test Equipment for Making Repairs. . 6-1 4. Removing the Signal Generator and Power Supply from the Cabinet. 6-1 a. Removing the RF Signal Generator SG-44B/URM-25 from the Cabinet. 6-2 b. Removing the Power Supply PP- 562A/URM-25 from the Cabinet. 6-2 5. Removal and Replacement of Parts. 6-2 6. Replacing RF Oscillator Circuit Components. .