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R1155 Manual Extracts
T1154 Manual Extracts
R1155 Photos
T1154 Photos
R1155 conversion to Civilian use
Links to other web pages on these sets
Chart 1 - shows the general arrangement of the various components including the D/F equipment, antennas and power supplies.
Chart 2 - is a simplified circuit of the T1154 transmitter.
Chart 3 - gives a block diagram of the R1155 receiver
Chart 4 - contains a simplified circuit of the communications component of the R1155 and
Chart 5 - has the circuit for the Range 3 (M/F) condition whilst
Chart 6 - shows the D/F circuits.
Chart 7 - is the final diagram covering the interconnection wiring of the main components.
| Switch Pos | 1 L/F | 1 L/F | 2 L/F | 2 M/F | 3 M/F | 3 H/F | 4 H/F | 5 H/F |
| Freq Mhz | 0.075 - 0.2 | 0.2 - 0.5 | 0.2 - 0.5 | 0.6 - 1.5 | 0.6 - 1.5 | 1.5 - 3.0 | 3.0 - 7.5 | 7.5 - 18.5 |
| Group | 1 | 2 | 1 | 2 | 1 | 2 | 1,2 | 1,2 |
| Model | Usage | Freq Group | Al/Fe Case | Comments |
| 1155 | Air | 1 | Al | Original model |
| A | Air | 1 | Al | Filters type 1 |
| B | Air | 1 | Al | Filters type 2 |
| C | Air | 1 | Al | As A with H/F D/F |
| D | Air | 1 | Steel | As R1155 |
| E | Air | 1 | Steel | As A |
| F | Air | 1 | Steel | As B |
| L | Air | 2 | Al | Coastal Command |
| M | Land | 1 | Al | Land as poor quality solder |
| N | Sea | 2 | Steel | High Speed Launch |
The extracts shown here are only a small part of the R1155 manual (AP2548A Chapter 2) but have been selected for their interest value. All have been scanned as A4 sheets.
Page 1 - is a view of the receiver from the manual.
Page 2 - gives general specifications of the R1155.
Page 3 - allows the various model types to be identified. Note that the L and N models were used for maritime work in Air Sea Rescue Launches and had different frequency ranges.
Page 4, Page 5, Page 6, Page 7 - each show part of the full circuit for models R1155, A, D, E & M.
Page 8, Page 9, Page 10 - show the index to and the 2 parts of the component location diagram.
Page 11, Page 12 Page 13 - show a typical installation diagram in an aircraft with a list of component numbers.
Page 14, Page 15 - illustrate the receiver fault finding chart which has had to be displayed as 2 pages.
Page 20, Page 21, Page 22, Page 23 - these pages list the components, showing circuit refs and their values.
Page 1 - gives general specifications of the T1154.
Page 2 - allows the various frequency ranges to be identified.
Page 3 - gives the main differences between the models.
Page 4 - shows the full circuit for model T1154L.
Below are a few detailed pictures of a number of variants. The most common types seem to be the A and B variants, those used in aircraft following the addition of filters for the Irish Athlone broadcast station close to the 560KHz IF frequency and for radar frequencies. The electrical differences between the various models are due to the increasing number of filters found to be necessary and a modified frequency coverage for those used in maritime services. Cosmetic differences include the tuning knobs, use of steel or aluminium for chassis and cases and the panel lettering (painted or attached plates).
The main tuning knob was redesigned when the earlier type was found to be awkward to use, especially when the operator wore gloves against the cold, as the fine tuning section was at the rear. The redesigned knob tends to be the more common since it was retro-fitted to earlier models and is pictured at right.
Many sets are found without some of the D/F controls and most without the D/F valves, since these were both officially removed from sets not used for navigation as well as by civvy buyers to reduce the heater current.
R1155 - front panel of the rare original version without filters. Shows cloudiness of the perspex dial and discolouration of screen printed labels, both faults being quite often found. Despite some of the caps looking very tired, this set operated well as received, though a new magic eye was fitted as the original was dim. The set perfoms better than the A and B models below. The case and front have been repainted in view of the amount of missing paint and corrosion.
R1155A - front panel, with replacement improved tuning knob fitted.
R1155B - the final model. This unit has been officially rebuilt with plastic wiring for the Australian airforce in the 1950s, apparently as a "make work" job in the AWA factory. Two wiring errors, neither critical, were found plus a shorted mica cap and a VR100 with internal shorting! One wiring error was a reversed voltage divider and the other connection of the magic eye to the AF rather than the RF volume control when not on AVC. The latter was too hard to get at to fix! Now works well down to 30V on the HT!
R1155B - showing the type of mounting brackets at the rear which were used in the RAAF Lincolns. Note the safety chains to restrain the set should the rubber shockmounts come unstuck from the steel, which some of mine had! These mounts have usually been removed.
R1155E - front panel of a steel cased version.
Many additional detailed pictures of these sets, including internal views can be seen at my R1155/T1154 Gallery
Here are front panel views of two main variants of the transmitter. On the left is the Bomber Command type of which the T1154M is an example and on the right the High Speed Launch type, the T1154L. The main differences are in the frequency range of the Blue band of which the most visible sign is the Ae tuning at the top right.
| Colour | Yellow | Blue | Red | Red | Blue | Blue | Blue |
| Freq Mhz | 0.2 - 0.5 | 1.5 - 3.0 | 2.5 - 4.5 | 3.0 - 5.5 | 4.5 - 8.7 | 5.5 - 10.0 | 8.7 - 16.7 |
| Group | 1,2,3,4 | 4 | 2,3 | 1,4 | 2,3 | 1 | 2 |
| Model | Usage | CW, MCW only | Freq Group | Click type | Al/Fe Case | Comments |
| 1154 | Air | N | 1 | Multi | Al | Original model |
| A | Air | Y | 1 | Multi | Al | Original model |
| B | Air | N | 1 | Multi | Al | Halifax only |
| C | Air | N | 2 | Multi | Al | Coastal Command |
| D | Land | N | 3 | Multi | Al | Early land mobile |
| E | Land | Y | 3 | Multi | Al | Early land mobile |
| F | Air | N | 2 | Multi | Al | Superceded C |
| H | Air | N | 2 | Uni | Al | Final Coastal Command model |
| J | Air | N | 1 | Multi | Steel | Steel Bomber version |
| K | Air | N | 2 | Multi | Steel | Steel Coastal Command version |
| L | Sea | N | 4 | Uni | Steel | High Speed Launch version |
| M | Air | N | 2 | Uni | Steel | Final bomber version |
| N | Air | N | 1 | Uni | Steel | Steel version of Halifax |
T1154M - general view of a T1154M for comparison. The main differencies are in the upper right hand controls. The M was the final aircraft version. This particular unit has been reconditioned for the Australian airforce in 1955 and modified to accept a 12 crystal control unit. Note top of the mounting brackets at the rear and the red slider switch to the right of the front cover which switches the crystal unit in and out.
Additional pictures of these sets, including internal views can be seen at my R1155/T1154 Gallery. Included in the gallery is the full size artwork for the front panel frequency charts for the groups 1, 2, 3 & 4 above.
The article consists of 5 pages Page 1, Page 2, Page 3, Page 4, Page 5 that you can view separately. They have been reduced in size to avoid excessive download times.
Replacement parts - G4CVU supplies replica parts for the R1155 and T1154 series equipment.
Duxford Radio Society's page giving a history of the development of the R1155 and T1154 by Marconi and other companies.
The No 19 Group website contains the full AP2548A official manual and detailed circuits covering both the T1154 & R1155 in PDF format.
The VMARS website contains substantial extracts from the AP2548A official manual for the R1155 in TIF format.
Ray Robinson's excellent description of the R1155 and his efforts in restoring one.
Peter Tranter's description of the complete rebuild of an R1155. Good general description.
Ben Nock's web site with some contemporary pictures of the radio section of a Lancaster.
PA0PZD's good mock up of the radio and navigation sections of a Lancaster bomber including the R1155 and T1154
